Fibre-optic system and measurement of turbo machine system parameters

FIELD: engines and pumps.

SUBSTANCE: proposed system comprises light source to transmit light onto shaft surface via multiple optic fibres made at multiple points nearby said surface in, in fact, axial direction between the ends of at least one shaft, high-temperature reflection probe built around fibre bundle to detect light reflected from shaft surface and mechanism to measure torque or oscillation at the shaft. The latter comprise coding mechanism composed of changed texture shaped to wedge-like groove on shaft surface of variable depth. Said depth generates the front and rear working point signals so that appropriate time delay can be detected from whatever two positions of said groove for determination of shaft twist angle by differentiation of reflection pattern characteristics during every rotation cycle.

EFFECT: higher precision of measurements.

23 cl, 24 dwg

 

The prior art inventions

The invention relates generally to fiber-optic system and method for measuring multiple parameters for monitoring the operating status turbomachine system and, in particular, to a system and method that enables to measure static and dynamic torque and vibration in Turbomachinery system.

Torque measurement turbomachine moments that change along its shaft, provide the design engineers with important information to validate and improve the efficiency of the system. In addition, the mechanical alignment is poor, the sliding friction between the rotor and stator, the curvature of the shafts, slip joints and other random forces usually result in static and dynamic torques on the rotors and shafts and Flexural and torsional vibrations, which cause the majority of failures. Torque and vibration are some of the critical parameters that can be measured to monitor the efficiency of energy generation or deterioration in turbomachines system, which may contain steam turbine, generator, power gear and the gas turbine. They can be measured using resistive strain gages, sensors stationary proximity, magnetostrictive and magnetoelastic sensor is impressive. These sensors are based on the rotation must be mounted on or near the surface of the rotor and the shaft, which is not always possible because of space limitations. The disadvantage of these traditional technologies of measurement is the effect of changes in environmental conditions, such as temperature, pressure, light, humidity and electromagnetic interference. Because typical turbomachine the system operates at temperatures from about 100°F to about 1200°F and high humidity, it is subjected to alternating torsional or Flexural vibrations and radial thermal expansion due to the large dynamic mechanical deformation and Flexural and torsional vibrations. They can affect the accuracy and lifetime of these measuring devices. Therefore, these measuring devices are not reliable when used for long periods at a major turbomachine.

Measurement of torque on the rotor and the shaft includes a determination of the power turbine or other rotating devices, generators or consumers. In industry ISO 9000 and other quality control specification required for measuring the torque at the time of manufacture, especially in the case of the use of fasteners. Currently there is not a practical measurement system, which could measure static and dynamic torque is oment turbomachine system, for example, the surface of the rotor and shaft of a steam turbine, whenever the place of measurement, it is necessary to perform measurement in harsh conditions.

Known optical torque measurement include the use of methods of deflection of the laser beam on the basis of free space for measuring the torque due to the reflection of the laser beam from the micromirrors are embedded in the surface of the shaft. Such devices are difficult to use in the environment of the steam turbine due to absorption of the laser beam ferry, and also due to the maintenance requirements of the optical surface of the micromirrors, which are sensitive to the environment of the steam flow, as well as to mechanical alignment and vibration.

Such a known system for measuring vibration on the basis of optical interference measure mechanical deformation and displacement, but these systems are not intended for Turbomachinery system to ensure that mechanical deformation of the rotor shaft of a steam turbine associated with the detected vibration, since thermal expansion complicates maintaining optical focusing and signal integrity in a dynamic environment.

All modern technologies, such as sensors stationary proximity, resistive strain gauges, magnetostrictive and magnetoelastic sensors, not reliable on the I steady work in turbomachines system, for example in the environment of a steam turbine, during the life of the equipment, and they are all sensitive to temperature. This property of sensitivity to temperature causes serious problems of reliability and leads to loss of precision.

Another problem associated with modern technology, refers to the installation options these traditional devices for measuring torque/vibration in Turbomachinery system, for example in the environment of a steam turbine, including, without limitation, humidity, pressure, variable electromagnetic interference, temperature within 100 -1200°F, and Flexural or torsional vibration of the rotor. Load cell, for example, must be installed on the surface of the rotor, and a magnetostrictive sensor must be installed near the surface of the shaft in the gap or clearance is less than a few hundred microns. Temperature fluctuations in turbomachines system, such as the different stages of a steam turbine, generating significant transient thermal expansion and Flexural or torsional vibration of the rotor. In harsh environmental conditions reliable measurement of torque and vibration between the steam turbine and generator, between the generator and the power gear and between the power gear and a gas turbine and a separate stages of the steam turbine will be able to trace the product is italmost and a more optimal schedule repairs, maximising the capacity and efficiency of the turbine.

In addition, Flexural and torsional vibrations caused by shifts of the load between the steam turbine and generator, between the generator and the power gear and between the power gear and the gas turbine can generate transient fluctuations that exceed the voltage level steady state under full load. Such transient nonlinear oscillations can lead to bearing wear, bending deformation of the shaft and a high torque load, it threatens the stability of the system energy generation based on steam turbines, among other effects. Traditional vibration measurement, for example using accelerometers, strain gages, probes proximity and tachometers, may be limited or harsh environmental conditions of the steam turbine, including, without limitation, temperature, pressure, steam, dust particles, humidity and high consumption, or their nature as contact and electrical measuring devices.

In normal operating conditions of the shaft, which correspond to the state of equilibrium, the observed low-frequency random vibration signal, although small, may be the result of friction during movement between the rotor and stator, the curvature of the shafts, slip joints and other random the forces. Flexural modes of vibration due to mechanical alignment is poor rotating system, temperature distribution and imbalance; whereas the torsional vibration can be caused by the dynamics of the torque caused by the state change of the load shaft, and transient changes in the speed of rotation. External unknown force excitation, transient switching capacity and unstable operation of the whole system can also generate transient nonlinear fashion vibrations that can have high vibration amplitudes. In addition, the deterioration of the turbine blades reduces recoil and can be tracked by reducing the frequency of change of torque and vibration.

In view of the foregoing, it would be mostly useful to provide a practical solution for rapid analysis of the torque and vibration turbomachine system, for example a steam turbine, to improve the performance of energy generation, as well as control and optimize the efficiency of energy generation. This solution should provide a reliable means to measure static and dynamic torque, linear and nonlinear vibrations on rotating shafts or reliable means of diagnosing and predicting failures. Reliable measurement of torque and vibration between the sections t is rbine and between the individual turbine stages in turbomachines system will allow you to track performance and a more optimal schedule repairs, maximizing the efficiency of energy generation Turbomachinery system. It would also be predominantly, if the system and method to measure static and dynamic torque turbomachine system also can be easily adapted for reliable measurement of linear and nonlinear characteristics of the vibration of the shaft.

The invention

Mechanical alignment is poor, the sliding friction between the rotor and stator, the curvature of the shafts, slip joints and other random forces usually result in static and dynamic torques on the rotors and shafts; then as the load shifts between the steam turbine and generator, between the generator and the power gear and between the power gear and the gas turbine can generate transient Flexural and torsional oscillations, which can exceed the voltage level steady state under full load. In turn, such transient nonlinear oscillations can also cause bearing wear, bending deformation of the shaft and a high torque load, it threatens the stability of the system energy generation based on steam turbines, among other effects.

Improvement and optimization of the efficiency of energy generation, diagnostics and forecasting of failures for Turbomachinery systems subject is onitoring through operational measurement system. As described here the implementation provide a reliable means to measure static and dynamic torque, linear and nonlinear vibrations on rotating shafts or inside the steam turbine between the steam turbine and generator, between the generator and the power gear or between the power gear and the gas turbine. Any decision must also be practical for the installation of the probe in harsh environmental conditions, which can satisfy the desired operating state temperature, humidity, pressure, flow rate, etc.

Measurements of transmittance and reflectance on the optical fiber base can be used for different measurement applications. To deliver the light and remove the signal passes through a sealed cables. More importantly, signals, measurements, or to obtain static and dynamic parameters, such as torque, or to obtain the linear and nonlinear parameters such as Flexural and torsional modes of vibration, it is necessary to decode and parse.

There is therefore a need in the software deployed in the operating conditions tightly Packed fiber probe, system and method for measuring multiple parameters and solutions for the installation, suitable for simultaneous measurement distribution is Lenna, stationary and dynamic parameters in extremely harsh environmental conditions, for example in turbomachines the system as a whole and in the steam turbine, in particular.

One variant of implementation of the present invention includes a beam splitter on the basis of a bundle of fibers. This optical device effectively divides light from a single light source for transmitting light in multiple places. The light source according to one variant of implementation, contains: lots of multimode fibers configured by random, indeterminate, regular or co-axial pattern. These fibers are connected to each other high-temperature ceramic adhesive and sealed with a metal material, for example stainless steel.

Another variant of implementation of the present invention includes a probe reflection on the basis of a bundle of fibers 1×2. This optical device effectively delivers the light source to the measuring and simultaneously measures the reflection on the surface of the shaft. It contains: a lot of multimode fibers configured by random, indeterminate, regular or co-axial pattern. These fibers are connected to each other high-temperature ceramic adhesive and sealed metallic material resistant to oxidation, such as Inconel. Part of the fibers of p is odnaznachno for delivery of light, and part of the fiber is intended for removal of signal measurements.

Another variant implementation of the invention includes a method for optical coding using embedded wedge-shaped grooves or periodic or aperiodic patterns created by micromachining processing, and straight lines drawn on the outer surface of the shaft. Aperiodic coding pattern is used to measure the static torque, while periodic or straight lines are used to detect dynamic torque and torsional vibration.

According to another variant implementation, provided by fiber-optical measuring system, which contains a light source capable of transmitting light in multiple places on the surface of the shaft turbomachine system through a bundle of optical fibers 1×N, and a multitude of locations on the surface of the shaft is located in essentially the axial direction between the ends, at least one shaft, making many dynamic reflected light signals received from multiple locations on the surface of the shaft when the at least one shaft-loaded; in which the reflected signal from anywhere is removed by means of a sealed probe reflection 1×2; and the signals from multiple probes reflected what I do on the matrix of photosensitive detectors for further analysis in the time domain and in frequency domain. Torque and torsional vibration are encoded either mechanically applied wedge-shaped grooves or patterns created by micromachining processing. One variant of implementation of fiber-optic measuring system contains a matrix of photosensitive detectors, capable of detecting dynamic light reflected from the surface, at least one shaft turbomachine system in response to a missed light during rotation, at least one shaft turbomachine system, and generate from it a dynamic signals reflected light. Torque on the shaft and vibration features are determined based on at least one characteristic of the reflected light signals received from the surface of the shaft encoding any of the continuous excitation light, either from the frequency-modulated light, and by processing the signal based on the synchronization.

According to another variant implementation, the fiber-optical measuring system for measuring the operating state turbomachine system associated with Flexural modes of vibration and nonlinear vibration, contains frequency-modulated light source capable of transmitting light in multiple places on the surface of the shaft turbomachine system via the optical connector 1×N, and the dynamic of the reflected light signals are taken using multiple sealed probes reflection 1×2, which are connected to the matrix of photosensitive detectors for signal analysis in the time domain and in frequency domain. Optic reflection probes are located in many locations near the surface of the shaft that does not require mechanical or optical encoding on the surface of the shaft. One way of implementing further comprises a matrix of photosensitive detectors, which can be a charge-coupled devices (CCD) or detectors based on the complementary structure of the metal-oxide-semiconductor (CMOS)capable of recording dynamic light reflected from the surface, at least one shaft turbomachine system in response to reflections from her dynamic light signals. The fast Fourier transform of the measured dynamic reflection is used to determine linear and nonlinear constants and instantaneous vibrational state turbomachine system.

Description of the drawings

These and other features, aspects and advantages of the present invention made it clear from the following detailed description, given with reference to the accompanying drawings, is supplied through a system of signs, in which:

figure 1 - fiber-optic instruments measure the torque and vibration for turbomachine system according to one variant of implementation is tvline invention;

2 is a diagram of a fiber-optic system for measuring torque on the basis of the phase shift for a steam turbine according to one variant embodiment of the invention;

figure 3 is an electronic diagram of the coding and signal processing for fiber-optical torque sensor according to one variant embodiment of the invention;

4 is a simplified diagram illustrating the technique of measurement of torque on the basis of multi-point differential phase shifts according to one variant embodiment of the invention;

5 is a diagram showing the condition of the width of the pulse light source for measuring torque according to one variant embodiment of the invention;

6 is a diagram showing the source signals and the signals of the static and dynamic torque, measured by changing the width of the input pulse light source according to one variant embodiment of the invention;

Fig.7. diagram of the branched beam of fibers to deliver the light source to the multiple reflection probes according to one variant embodiment of the invention;

Fig diagram of the probe reflection configuration fibers 6x1 for delivery of light and its reception from the surface of the shaft according to one variant embodiment of the invention;

figure 9 - configuration of the distance of the probe is La detection of torque from the shaft surface and its corresponding operating points according to one variant embodiment of the invention;

figure 10 - levels of reflection in different operating points for the probe to detect the torque shown in Fig.9;

11 - the encoding of the shaft, which includes a line in the form of wedge-shaped grooves and straight lines according to specific variants of carrying out the invention;

Fig is a more detailed diagram of the three templates encoding the surface of the shaft, shown in figure 10;

Fig signals of the torque measurements from different coding patterns in one operating point;

Fig signals static torque from the different probes from the surface of the shaft encoded in straight lines within one cycle;

Fig signals static torque from the different probes from the surface of the shaft with the encoding of the wedge-shaped grooves within one cycle;

Fig is a graphical representation of the detection of the dynamic torque of the time delay between the first probe and the k-th probe as a function of time;

Fig is a graphical representation of the signal reflected from the surface of the shaft encoded periodic lines according to one variant embodiment of the invention;

Fig is a graphical representation of the measured torque and the corresponding twisting angle according to one variant embodiment of the invention;

Fig one section of fiber is pricheskoj of vibration monitoring systems for steam turbine according to one variant embodiment of the invention;

Fig technique of transmitting laser light signals through a bundle of optical fibers in four probe reflection and reception of multiple echoes from the four probes reflection in response to the transmission of signals according to one variant embodiment of the invention;

Fig - principles of signal detection dynamic Flexural vibration on the basis of reflection according to one variant embodiment of the invention;

Fig - tech multipoint detection signal dynamic torsional vibration on the basis of reflection according to one variant embodiment of the invention;

Fig - multipoint signal dynamic torsional vibration based on the reflections in the time domain according to one variant embodiment of the invention; and

Fig - multipoint range of dynamic torsional vibration based on the reflection from the probe according to one variant embodiment of the invention.

Although the above mentioned drawings shows an alternative implementation options, you can offer other embodiments of the present invention mentioned in the description. In any case, this disclosure is illustrative embodiments of the present invention in the order of presentation, but not as a limitation. Specialists in this field of technology can offer many other modifications of the embodiments of, to meet the extent and nature of the principles of this invention.

Detailed description

Here is described a fiber-optic system to measure static and dynamic torque and vibration in harsh environmental conditions according to one variant of implementation to improve the efficiency of energy generation Turbomachinery system or monitoring deterioration and possible failure. Unlike traditional temperature-sensitive sensors stationary proximity, magnetostrictive and magnetoelastic sensors described herein embodiments of a fiber-optic multiparameter measuring system is insensitive to temperature and multiplexed probes based on extensive bundle of fibers, which are either distributed to different levels of pressure in a steam turbine, or deployed between the steam turbine and generator, between the generator and the power gear, between the power gear and the gas turbine and/or between the compressor stages, for multipoint monitoring design turbomachine system.

For example, figure 1 shows a fiber-optical devices 200 measurement of torque and vibration for turbomachine system according to one variant embodiment of the invention. Fiber-optical devices 20 measurement of torque and vibration capable of multi-point monitoring the operating status of the turbomachine in the steam turbine 202, between the steam turbine 202 and generator 204, between the generator 204 and the power reducer 206, between the power gear 206 and the gas turbine 208 and within the gas turbine 208. Fiber-optical measuring system can be locally distributed either a steam turbine or gas turbine, or, in General, distributed in turbomachines system from the steam turbine, through the generator, the power reducer to the gas turbine for failure diagnostics, forecasting and long-term performance monitoring.

One variant of implementation of fiber-optic measuring system described hereinafter with reference to figure 2, for probes on the basis of a bundle of multiple fibers that are installed along the surface 24 of the shaft, includes a source 12 multi-color light (for example, lasers with multiple wavelengths or broadband LED)emitting light in the visible (405-671 nm) or near infrared (1.0-1.7 µm) band, which is either modulated pulses of microsecond duration, or is used in continuous mode. The light source is divided into multiple branch optical splitter 1×N and arrives in different areas 14, 16, 18, 20 on the surface 24 of the shaft of the turbomachine, each region includes either an optical or mechanical encoding mechanism 38, Vysokoe the temperature probes 26, 28, 30, 32 reflections on the basis of a bundle of fibers 1×2, are used to signal reflections near the surface of the shaft and transmit these signals to the matrix 34 of light-sensitive detectors and the block 36 signal processing. If the light source is modulated, synchronous multi-channel amplifier reference provides the necessary handshaking between the matrix 34 high-speed photodiode detectors and multi-color light source 12.

The light source may be a continuous wave that allows all the probes 26, 28, 30, 32 reflections register signature of the maximum reflection from the surface 14, 16, 18, 20 of the shaft with optical encoding. Static signal reflected from the surface, at least one shaft turbomachine system, analyzed by differentiation signatures reflection of any two signals of the probe. Static(s) twisting of the shaft or torque is determined from the difference between the signatures of the optical encoded signals of any two probes reflection.

The duration of the first light signal is modulated so that all of the probes 26, 28, 30, 32 reflections could register a maximum difference of reflection from the encoders 38 of the shaft surface. Dynamic signal reflected from the surface, at least one shaft turbomachine system is analyzed by differentiation of delay on the straps between any two signals of the probe. The time delay is determined by the signature of reflection, induced shaft with the encoding from any two probes reflection. Then the dynamic torque on the shaft is determined based on the speed of rotation of the shaft and the elastic modulus of the material of the shaft.

The indication provided by the system 10 to measure dynamic torque is that torque can be detected either by modulating the duration of the light pulse, so that it was equal to the time required for registration time delay induced torque, or by differentiation of increasing the time delay of the signal coming from the edges of the highly reflective strips encoding on the surface 24 of the shaft of the turbomachine. In addition, fast Fourier transform on the signal signatures reflection can provide rapid analysis of how to torsional modes of vibration, and the vibration modes associated with failure.

Another feature provided by the system 10 to measure static and dynamic torque, is that its definition of torque on the basis of the phase does not depend on the intensity of the reflected signal and therefore does not have a negative impact due to the deterioration of the reflection or the fluctuations in light scattering due to corrosion, erosion, surface of the shaft or dirt on the optical path between the probes 26, 28, 30, 32 reflection and encoders 38 of the shaft surface.

The third sign is associated with a relatively large clearance (1-10 mm) between the surface 24 of the shaft of the turbomachine and probes 26, 28, 30, 32 reflections, which provides a convenient method of installation, allowing bending or torsional vibration and the radial thermal expansion of the rotor of the turbomachine.

Another feature provided by the system 10 to measure static and dynamic torque, is that the source 12 lighting with multiple wavelengths, which ensures that the torque measurement is insensitive to moisture, mineral oil and dirt through the simultaneous differential measurement of torque with two or multiple wavelengths of light sources. On the other hand, coders surface of the shaft, surrounding the outer surface of the shaft, further weaken the possible distorted signatures reflection of a dirty encoder.

One version of the exercise system 10 of the torque measurement demonstrates the measurement of torque with best resolution of 0.05 degrees during operation at room temperature, and the resolution should be better than 0.1 degrees at a temperature of about 1200°F.

In a brief explanation, optical fiber measuring system 10 provides a standalone tool, which is you can simply install in turbomachines system, for example, a steam turbine, for monitoring the torque of the rotor on the shaft at different levels of pressure. The main components of this tool are the light source (for example, multicolor laser or a broadband LED) 12, a branched fiber-optical divider 22, the matrix 26, 28, 30, 32 high-temperature probes reflect the 1×2 matrix 34 of light-sensitive detectors, the processor 36 of the signal and the appropriate software signal processing. The surface of the shaft encoding provides such fiber-optical measuring system for measuring critical parameters, such as static torque, dynamic torque and torsional vibration of the rotor. Other signs include:

Fiber-optical measuring system 10 is a technology-based multiplexing wavelength-integrated with the processing of the encoded signal based on the phase shift and FFT. The measuring signal is fed to and from the surface 24 of the shaft encoded through the fibers 26, 28, 30 and 32, resistant to high temperatures, to provide a method of monitoring the operational state of the shaft, which is passive to any transition of power fluctuations induced electromagnetic interference.

Simultaneous detection torque is omenta and torsional vibrations provides "static" and "dynamic" methods of measurement using a single fiber-optic measurement system reflection, which can be reduced to the subsystem, for example a steam turbine, or extended to the whole of Turbomachinery system of the power plant. The combination of static and dynamic response provides a unique solution to overcome the problems of modern stationary sensor proximity, resistive strain sensor, magnetostrictive and magnetoelastic sensor associated with the drift of the original signal and frequent recalibration, as well as problems of electromagnetic interference.

Because turbomachine system includes a steam turbine, gas turbine and generator, the majority of these subsystems operate at temperatures from room temperature up to about 1200°F at a variable pressure, variable vibration and thermal expansion of the rotor, which can have a serious impact on the reliability of the use of these measuring devices. The probes 26, 28, 30, 32 for detecting reflection on the basis of extensive bundle of fibers can withstand high temperature and pressure and is flexible enough to be installed in any location on the surface of the shaft; and, therefore, provides a method of monitoring, insensitive to environmental conditions.

Fiber-optic probes 26, 28, 30, 32 for measuring the reflectance can be set in the form of a matrix, and therefore a single laser or LED light source can be divided into many individual p is x probe providing higher spatial resolution measurements. Thus, fiber-optical measuring system 10 is ideal for applications that require either a localized measurement, or large-scale multipoint monitoring the operational state of the shaft with high spatial resolution, for example, associated with the stages of a high pressure (HP), intermediate pressure (IP) and low pressure (LP) steam turbine.

The use of light beams of multiple wavelengths in the system allows you to more reliably track the condition of the shaft by simultaneous differentiation of the measurement signals at different wavelengths, despite the fact that mineral oil, dirt or corroded surfaces can create problems. The reason is that the wavelength can feel strong absorption of these pollutants, which can lead to the weakening or even loss of signals, while other wavelengths may experience minor absorption, so the differential of two weakly absorbed beams can provide a reliable way of measuring the parameter in harsh environmental conditions.

The time delay of the mechanism 38 of the optical encoding (for example, reflective strips encoding of the shaft) and the cross-correlation and filtering FFT-based signal sensor is through the processor 36 of the signal to recover the envelope of the noise and the carrier of the cross-correlation function provides the technology for operational analysis and monitoring of static and dynamic torque in real-time. According to one variant of implementation, the reflective strips encoding of the shaft surface with a number of evenly spaced lines create periodically strobirovaniya signals of zero frequency + carrier signals from each probe reflection. According to another variant implementation, the reflective strips encoding of the shaft surface with a number of frequency-modulated, or unevenly spaced, to form a continuous frequency-modulated carrier signal from each probe reflection. This template is coded signal provides a unique signature of reflection for static and dynamic measurement parameters, for example, torque and torsional modes of vibration.

Cross-correlation and filtering FFT-based signal reflections for recovering the envelope of the noise carrier and cross-correlation functions mainly prevents any reduction in accuracy of measurement induced by a possible change of the reflection light beam. To do this, first get a rough offset from the envelope, and then adjusted the offset (within a half period of the carrier) from any phase shift of the carrier to determine the mechanical deformation that is associated with an angular offset, and twisting or angular displacement of the shaft. This technique not only provides monitoring is Oceania static and dynamic torque, but mainly provides a direct method for simultaneous measurement of torsional or Flexural vibration of the rotor of the FFT analysis of the signal with time delay.

Figure 3 shows an electronic circuit 70 coding and signal processing, suitable for use with fiber-optical measuring system 10 according to one variant embodiment of the invention. Together the above detection technology torque on the basis of the phase shift method and system 70 signal processing based on the FFT can be used for simultaneous detection of static and dynamic torque of the rotor with calibration, regardless of changes in ambient temperature and surface defects of the shaft due to corrosion and erosion, among other things.

In addition, the signature signal reflection, instead of the absolute intensity of the reflected light, the above analysis technology and method and circuit 70 signal processing based on the FFT can provide digitized responses based on the angular offset on the measurement parameter that is much safer than traditional analog technology based on the detection intensity or reflection. Branched fiber divider 22 and the above-described coaxial probes 26, 28, 30, 32 for measuring the torque on the system, which eliminates the need for optical alignment, which allows to significantly improve system performance and reduce maintenance requirements of the system.

Scheme 70 coding and signal processing creates periodically strobirovaniya signals of zero frequency + bearing aperiodic signals or frequency-modulated signals of zero frequency + carrier signals based on the reflected pulsed light signals (i.e. laser or LED), coming from the reflecting strips 38 of the shaft of the turbomachine, which is encoded according to one variant of implementation, the sequence of lines with a uniform or frequency modulation diversity for encoding information torque and torsional vibration. Mechanisms 38 optical encoding, according to one variant of implementation, associated with the wedge-shaped groove or a metal bar code that is embedded in the right places at the surface of the shaft 24, which reflect the incident light (i.e. laser or LED), as described above.

The surface of the shaft 24 of the turbomachine can be modified by changing, without limitation, surface texture to provide regions having different depths relative to other areas of the surface of the shaft. The mechanism 38 of the optical encoding can be implemented, for example, by forming a wedge-Kahn is Cai on the surface of the shaft in the right places, to the corresponding time delay can be detected from any two provisions of the wedge-shaped grooves to determine the value of the twisting angle of the shaft, which can be used to determine the torque on the shaft.

The mechanism of optical encoding deposited on or embedded in the shaft of the turbomachine, it is also possible to realize, without limitation, by merger or other periodic or aperiodic frequency modulation pattern or template of a straight line on or in the surface of the shaft in the right places, corresponding to a time delay can be detected.

The cross-correlation 64 and filter 66 FFT-based 68 signals 62 sensor is designed to restore the envelope of the noise carrier and cross-correlation functions for signal processing. A rough estimate (coarse offset) 76 derived from the envelope of the noise, whereas the adjusted offset (within a half period of the carrier) 72 deduced from the phase shift of the carrier to ensure the assessment of 74 phase shift high precision, which can then be used to support a precise definition of information desired twisting of the shaft and vibration.

The light is directed to the surface of the shaft 24 through the branched optical fiber-optical divider 22. The light source can be a, b is C restrictions LED light source, laser light source or a broadband light source, such as a source of white light or multi-color light source, which is resistant to contamination shaft, etc. that are described here in more detail. New or perfect shaft requires only a single wavelength of light to provide a system and method according to principles described here.

According to one variant of implementation, the fiber-optical divider 22 is a bundle of fibers, which receives light from the light source 12, as described above, and assigns (shares) in a separate optical fiber, leading to isolated areas of the surface 24 of the shaft of the turbomachine. Each tap of the divider is connected with the amplitude of the light, which is different from the amplitude associated with other branches of the divider due to the relative difference in distance between the bends, which must be distributed light. However, the wavelength will be the same for all branches, so the signature of light remains constant at the ends of branches. Passing multiple wavelengths of light through the fiber optic connector can occur simultaneously according to the principles described here. Fiber optic connector according to one variant of the implementation are described in more detail below with reference to Fig.7. This optical device comprises m is these multimode fibers, configured by random, indeterminate, regular or co-axial pattern. These fibers are connected to each other high-temperature ceramic adhesive and sealed by a metal material such as stainless steel (operating range up to 1500°F).

Each tap of the fiber optic connector is connected to the probe reflection 26, 28, 30, 32, which has a drainage drop/transfer and withdrawal of registration/measurement. The challenge of falling forwards/transmits incident light on the surface of the shaft, whereas the discharge of the measurement adopts a modified light reflected by the surface of the shaft in response to incident light. Each probe reflection is located near the surface of the shaft. One variant of implementation of the probe reflection described in more detail below with reference to Fig. Probe reflection on the basis of a bundle of fibers 1×2 contains many multimode fibers configured by random, indeterminate, regular or co-axial pattern. These fibers (operating range up to 2000°F) are related to each other high temperature metal adhesive (operating range up to 2000°F) and sealed metallic material resistant to oxidation, such as Inconel 625 (operating range up to 2100°F).

The challenge of measuring probe reflection is connected to the light-sensitive detection mechanism, for example the matrix 34 FD is datchikov, or CCD, or CMOS. The pattern of reflection of the reflected light on the need(s) length(s) of a wave is measured by means of photodetection, which generates the desired(e) signal(s).

The signal processing starts with the calibration of any difference between the reflected signals taken from different locations on the shaft of the turbomachine, so there is no measurable difference between the measured signals propagating along the fiber, when the shaft is stationary. So anything that can make an error in the measurement of torque, ejected from the calculation of torque.

Taking into account these patterns and principles, any applied torque will cause twisting of the shaft of the turbomachine, which leads to a change in the initial alignment between the probes reflection. Any change to the definition of reflection between fiber probes reflection is measured to extract the information signal, which can be used to determine a corresponding change in the twisting shaft is twisting) and its dynamic changes due to static and dynamic torques. Information required torque on the shaft torsion vibration (torque value) is determined from the value of the curl and its time dependence.

The torque value can op is adelite one of two methods. The first method involves calibration using torque sensors that meet adopted the gold standard, which connect the measured value twisting with absolute torque value using the lookup table. The second method provides an analytical approach using the formulas for calculating torque based on the measured values of curl and depends on such characteristics of the shaft, as the geometry, the modulus of elasticity of the material, etc. of Such formulas and the transfer function is built into the software signal processing.

The use is described here fiber optic devices mostly eliminates the need for special lenses, prisms, diffraction gratings and other similar devices required for optics in free space, in order to avoid alignment problems, problems related to a change in temperature, which affects the focal length, the focal length etc. Use is described here fiber optic mechanisms also allow to solve the issues related to the mechanical properties, temperature-dependent, the holders of optical lenses, gradation and metal parts.

The determination of the values of torque on the basis of the phase measurement can Pref is going to uncertainties among the measured signals. These uncertainties can be reduced, according to one variant of implementation, using processing techniques signatures reflect the encoded optical signal, as described above with reference to figure 3.

The use of fiber optics and distributed techniques of measurement, such as described here, mainly allows you to use one set of devices to eliminate the need for a separate detectors. A broadband light source having multiple wavelengths, can be used to implement multiparameter measuring system, which can penetrate into the different types of pollution of the shaft, which may occur over time, according to the above-described variants of the invention. In addition, the use described here branched bundles of fibers provides reliable measuring system that is impervious, without limitation, to high temperatures, moisture and chemical vapors, for example, associated with failure of the optical system of free space, which can lead to fouling and defocusing lenses.

Figure 4 shows a simplified diagram illustrating the technique of measurement of torque on the basis of multi-point differential phase shifts according to one variant embodiment of the invention. The surface 24 VA is and turbomachine includes one or more coded reflective strips 38 with a number of evenly spaced lines according to one aspect of the invention. Torque applied to the shaft 24 of the turbomachine, leads to twisting of the shaft, which causes the angular displacement of the shaft 40 24.

Branched fiber bundles 42, 44 provide a transmission medium for the propagation of pulsed laser beams to the surface 24 of the shaft and for receiving therefrom the reflected signals. The reflected signals, the photosensitive detector 34, as shown in figure 2. The phase shift between the two probes of reflection can be identified by the difference in time relative to their positions of maximum reflection peak in the time domain.

The original or initial time signal 48 is measured on the basis of the pulsed laser beam through the optical fiber 42. Another signal 50 with a time delay is measured on the basis of the pulsed laser beam through the optical fiber 44. In particular, the offset 40 torque is determined based on the difference of time delays between received reflected signals in response to pulsed laser beams transmitted to the surface 14, 16, 18, 20 of the shaft encoding, etc.

Offset 40 torque reflecting () strip(s) 38 can be represented as

Offset torque Δα = Δtν, where Δt is the time difference and ν is the angular velocity of rotation of the shaft. The actual phase shift can be represented as

Phase the motor θ = Δα/R, where θ is the angular displacement of the reflecting () strips(approx) 38 and R is the corresponding radius of the shaft.

Since multiple points are measured on the surface 24 of the shaft, all the detected signals can be electronically strobirovat time to get all phase shifts that correspond to torque in different places.

Figure 5 shows a diagram showing the condition of the width of the pulse light source for measuring torque according to one variant embodiment of the invention. You can see that the length of time τ of the applied light source plays a role when determining the offset torque Δα. In practice, a continuous light source can also be used to detect torque, where the time delay is obtained by differentiation of the signature signal reflections in the time domain from two spaced probes reflection. In the simplest case, this signature corresponds to the peak maximum reflection when the reflected signal is dropcopy profile. In another case, this signature corresponds to one or multiple podpican of the envelope of a wave packet, which comes from periodic or aperiodic optical encoding mechanism. However, the use of a pulsed light source is more suitable for the of poverhnosti shaft, contaminated with rust or dirt in order to avoid spurious signals from irregular surfaces of the shaft and, thus, provides a more reliable method for the diagnosis and prediction of failures turbomachine system.

Simultaneous detection time delay and torsional vibration of the rotor provides a measure static and dynamic torque by using the above-described single fiber-optic system for measuring torque. This combination of two perceived response provides a new solution, which overcomes the problems associated with modern stationary sensors proximity, strain gauges, magnetostrictive and magnetoelastic sensors, including, without limitation, the drift of the original signal and the need for frequent recalibration.

Figure 6 rendered diagram illustrating a set of source signals 80 from multiple probes reflection on the basis of a bundle of fibers, as well as signals 82 with time delay induced static and dynamic torque, measured by changing the width of the input pulse light source, as shown in figure 5, according to one variant embodiment of the invention. The strobing of the light source is configured in time to capture signals of static and dynamic torque.

On Phi is .7 shows a diagram of the divider 90 or 22 on the basis of extensive bundle of fibers, shown in figure 2, for delivery of the light source 12 on multiple probes reflection according to one variant embodiment of the invention. Here, the divided optical fibers 92 can be set in the form of a matrix; and therefore, a single laser light source 12 can be divided into many separate probes 94 transmission, providing higher spatial resolution measurements. Therefore, the measuring system 10 is suitable for applications that require multi-point and multi-parameter monitoring with high spatial resolution, such as speed HP, IP and LP steam turbine or turbomachine system as a whole.

According to figure 2, the fiber-optical measuring system 10 applies the differential simultaneous multiparameter measurement or with three separate and different wavelengths of laser light or broadband light-emitting diode. Fiber-optical measuring system 10 can be used in online applications turbomachine system, including, without limitation, steam turbine, monitoring and control of mechanical deformation of the rotor shaft (static and dynamic torque, bending vibration of the rotor and so on) to improve the efficiency of energy generation. Fiber-optical measuring system 10 more sustainable and nadendla applications measuring operating state of the rotating system, than the well-known temperature-sensitive sensors stationary proximity, magnetostrictive and magnetoelastic sensors. Fiber-optical measuring system 10, for example, can operate at temperatures of about 1200°F, higher than those at which many famous traditional devices and systems measurement of torque as the probe, i.e. the fiber plus the casing can withstand high temperature operation.

On Fig shows a diagram of the probe 100 reflection 1×2 configuration fibers 6x1 for delivery of light and receiving reflected light from the surface 24 of the shaft, according to one variant of the invention, which is suitable for use in fiber-optical measuring system 10 for implementing high-temperature probes 26, 28, 30 and 32 on the basis of a bundle of fibers for measuring reflection shown in figure 2, in contrast to the structures of a fiber Bragg grating or long-period grating, which makes the system 10 is ideal for the registration of static and/or dynamic parameters. Central fiber 102 is used to deliver the laser beam from the optical divider and six coaxial fibers 104 are used to signal scattering from the surface 24 of the rotor shaft encoded on one element of the matrix of photosensitive detection 34. Dina branched structure of the coaxial beam of fibers 6x1 mainly replaces the accelerometer as a probe for measuring the Flexural vibration of the rotor to allow for the simultaneous detection of torque and torsional and Flexural modes of vibration using a single measuring device. The branched structure of the coaxial beam of fibers 6x1 mainly effectively permit requirements multiplexing while significantly reducing the cost of the system compared to conventional systems measure the torque.

The probe 100 for detecting reflection can be configured in one of many configurations of fibers, for example casual, half-hearted, coaxial and the other for delivery of light and receiving reflected light from the surface 24 of the shaft according to one variant embodiment of the invention. Such a probe 100 for detecting reflection provides a solution for the detection of static and/or dynamic torque, as well as for the detection of torsional and bending vibration level LP, IP and HP steam turbine. Such a probe 100 for detecting reflection suitable for multiparameter and multipoint diagnostics and forecasting operational status turbomachine system.

Described here, the light source with multiple wavelengths and the methods and systems of measurement of the phase shift on the basis of the reflection does not depend on the absolute reflectance and the efficiency of the scattering surface of the rotor shaft. These methods and systems, in contrast, is based on coded signatures reflect growing(delay(s) time signal, induced by the contrast, and phase shifts, as well as the frequency signatures. These detection and differentiation signature pattern significantly weaken the fluctuation of the reflection-induced defects on the surface of the shaft, including, without limitation, corrosion/erosion, oil or water that is not achievable using known methods and systems for measuring torque. In addition, the described structure of the high-temperature probe reflection based on the Packed bundle of fibers are immune to an internal temperature fluctuations of the steam turbine, which would otherwise affect the accuracy of the torque measurement, since the fluctuation of the reflection induced by thermal radiation is negligible when T<1200°F.

Described here is the structure of the high-temperature probe-based Packed bundle of fibers can also use random, incomplete and coaxial configuration of the fiber, so that the openings of the shaft from about 1 mm to about 10 mm can ensure maximum flexibility and stability and reduce the Flexural rotor vibration and thermal expansion, and mechanical deformation of the shaft, depending on temperature and pressure. The fibers in each bundle of fibers, according to one variant of implementation, has a diameter in the range from 50 microns in diameter, the re up to several hundred microns in diameter with a surface, metallic Ni, Ti, or Au for T>1000°F, or polyimide surface for T<800°F. These fibers are connected to each other and sealed in a metal tube with a metal adhesive that withstands 2000°F.

Figure 9 shows the detection signal from the probe 104 to detect a reflection on the distance d 106 from the surface of the shaft 24 and its corresponding operating point 108 or 110 according to one variant embodiment of the invention. Probe reflection can be installed on two typical distances from the surface of the shaft, wherein the first working distance 108 provides high sensitivity at short distances, while the second working distance 110 allows positioning the probe further away from the surface of the shaft. These working distances can detect fljuktuirujushchee dynamic displacement of the Flexural vibration, thermal expansion and nonlinear failure of the shaft.

Figure 10 shows the levels of reflection in different operating points for the probe to detect the torque shown in Fig.9.

Figure 11 shows the encoding surface 24 of the shaft at 90°intervals, including line 112 in the form of wedge-shaped grooves and straight lines 114 in accordance with the specific variants of the invention, which is suitable for realization of optical encoding 38, shown in Fig.. These encoders can be distributed over the outer surface of the shaft under any of the defined angles of 360°, 180°, 90°, 60°, 30° etc.

On Fig shows a more detailed diagram of the three templates 120, 122, 124 encoding the surface of the shaft, suitable for implementation lines 112 in the form of wedge-shaped grooves and straight lines 114, shown figure 11. Wedge-shaped groove may be created during laser micromachining processing or laser marking directly on the surface of the shaft; two other ways can also be based on the process of laser micromachining processing or labeling to create either a straight line or periodic and aperiodic frequency-modulated straight lines on the CrMoV steel sheet for section HP/IP and NiCrMoV steel for the LP section. In the connections pane for torque measuring section, the shaft diameter is usually from 10” to 30” in diameter. The required size of the coding sheet should be 10 mm (length) × 5 mm (width) × 0.1 mm (thickness), where the section thickness of the sheet metal must create a significant change in the signature signal reflection.

On Fig shows the signals of the torque measurements from different coding patterns, including signals 130 measurements from the surface of the shaft encoded periodic or frequency-modulated by straight lines and signals 132 measuring the t surface of the shaft with the encoding of the wedge-shaped grooves, both within a single cycle in the back of the working point 110 figure 10. In the frequency domain the natural frequency of the shaft rotation should be 30-60 Hz for a rotating system 1800-3600 rpm For optical encoding of each quarter section four labels encoding usually have a constant time delay between them. Static torque, transient torque and vibration can cause changes in these time delays over time depending on the operational working conditions turbomachine system.

On Fig shows the signals 130 with time delay associated with the different probes reflection in accordance with the surface of the shaft encoded periodic or frequency-modulated by straight lines within one cycle to detect static and dynamic torque.

On Fig shows the signals 132 static and dynamic torque associated with different probes in accordance with the surface of the shaft with the encoding of the wedge-shaped grooves within one cycle.

On Fig shows a graphical representation of signal 134 detection dynamic torque on the basis of the time delay between the first probe and the k-th probe as a function of time from Fig and 15, according to one variant embodiment of the invention. Here, the average signal p is ecstasy the value of the static torque.

On Fig shows a graphical representation of the reflected signal 140 from the surface of the shaft encoded periodic or frequency-modulated by straight lines 142 according to one variant embodiment of the invention. The measured signal reflection from 140 periodic straight lines shows how the signature signal reflection periodically modulated by means of optical encoding. To measure the static torque acting on the shaft, preferably encoding the frequency-modulated by straight lines.

On Fig shows a graphical representation of the measured torque and the corresponding twisting angle according to one variant embodiment of the invention. The principles described above with reference to figure 1-18, which can also be used, as described below with reference to Fig-24 for monitoring the bending and torsion (linear and non-linear vibrations of the shafts of the turbine-generator, which can generate transient fluctuations that exceed the voltage level steady state under full load.

Fiber optic multiparameter measuring instrument turbomachine system, described in more detail below, is useful for monitoring the bending and torsional vibrations of rotors and shafts in different sections, which can generate transient stake the project, which exceed the voltage level steady state under full load, as described above. Such transient nonlinear oscillations can lead to bearing wear, bending deformation of the shaft and a high torque load, it threatens the stability of the system energy generation based on steam turbines, among others. Traditional vibration measurement, for example, using accelerometers, strain gages, probes proximity and tachometers may be limited or harsh environmental conditions of the steam turbine, including, without limitation, temperature, pressure, steam or humidity and high consumption, or their nature as contact and electrical measuring devices. Embodiments of the fiber-optic system for measuring the torque and vibration, described below with reference to Fig-23 are for the diagnosis and prediction of failures for Turbomachinery system, which mainly insensitive to temperature and is not affected by electromagnetic interference.

On Fig shows one section of a fiber-optical system 210 vibration monitoring for steam turbines 212 according to one variant embodiment of the invention. The measurement mechanism is implemented in the form of branched beams 214 fibers that transmit light with multiple lengths in the us, for example laser beams to the surface 216 of the shaft with optical encoding and also take dynamic signals reflected from the surface 216 of the shaft to a high speed photodetector matrix 218. The source of the incident light is periodically modulated; and adopted a dynamic signals reflected from the surface 216 of the shaft with optical encoding of the detected high-speed photodetector matrix 218. Signals detected reflections are analyzed by a multichannel data acquisition system according to one variant embodiment of the invention.

Flexural and torsional vibration are obtained on the basis of spectral analysis of dynamic signals of reflection using the method of fast Fourier transform in accordance with the basic own frequencies of the rotation shaft of the harmonic components of higher order. In particular, transient torsional fashion, which correspond to periods of tension with relatively high amplitudes, it is possible to identify the instantaneous high frequency oscillations, described in detail below.

Described here are methods and devices for measuring the vibration can also be used to measure the dynamics of the transient nonlinear torque on the shaft, as described above, and which may be associated with failures of transmission lines. Signs of the techniques described here to change the mode of vibration relate to the exclusion of any contact requirements and insensitivity to humidity, pressure and dynamics of flow of the fuel/gas. Other signs include, without limitation, the simultaneous detection of the vibration signals and the corresponding nonlinear effects associated with the diagnosis and prediction of failures turbomachine system.

A significant advantage provided is described here techniques and topologies of the vibration system, refers to the distribution of multiple probes in turbomachines system, which can operate at temperatures up to about 1200°F.

Although specific embodiments of described herein for systems and methods of detecting vibration, the shaft surface with optical encoding described above to measure static and dynamic torque may be needed to detect characteristics of the Flexural vibration, although needed to detect the characteristics of the torsional vibration. The fact that the signal measurement for vibration is analyzed in the frequency domain by observing the basic frequency of the fashion of the shaft in the harmonic components of higher order, as specified above.

On Fig shows the technique of transmitting laser light signals 220 through the beam 226 optical fibers and receiving multiple reflected signals 224 in response to the transmission of signals, according to one variant of implementation of the invented who I am. Devices and mechanisms described in Fig form a multi-point, non-Intrusive operating system monitoring and diagnostics Flexural/torsional vibration, which can detect a range of frequencies of the fundamental natural frequencies of the rotation shaft of the harmonic components of higher order, which are a common form of defect of the shaft of a steam turbine-generator. The resulting system provides signal analysis dynamic torque method fast Fourier transform (FFT) of the measured dynamic reflection from the surface of the shaft with optical encoding, as described above. The measuring device includes an optical divider 226 on the basis of extensive bundles of fibers that conduct laser beams with multiple wavelengths to the surface of the shaft, and probes 228 for detecting reflections accept dynamic signals reflected from the surface of the shaft and pass on photodetector matrix 230, according to one variant of implementation. The incident laser beams periodically modulated continuous waves in the kHz square wave; and adopted a dynamic reflection signals detected high-speed photodetector matrix 230. Then, the detected signals are analyzed by a multichannel data acquisition system according to one variant of implementation.

the normal operating conditions of the shaft, which correspond to the state of equilibrium, the observed low-frequency random vibration signal, although small, may be the result of friction during movement between the rotor and stator, the curvature of the shafts, slip joints and other random forces. Flexural modes of vibration due to mechanical alignment is poor rotating system, imbalance, temperature distribution and pre-bend; whereas the torsional vibration may be the result of the dynamics of the torque caused by the state change of the load shaft, and transient changes in the speed of rotation. External unknown force excitation, transient switching capacity and unstable operation of the whole system can also generate transient nonlinear fashion vibrations that can have high amplitude vibration.

On Fig shows the principles of the detection signal of the dynamic Flexural vibration on the basis of reflection according to one variant embodiment of the invention. The surface of the shaft encoding, for example, discussed above, is not required to measure random and bending vibrations, because the spectral frequency domain analysis of dynamic reflection can itself be used to determine the normal load as described above.

On Fig shows ehnika multipoint detection signal dynamic torsional vibration on the basis of reflection according to one variant embodiment of the invention. It is advisable to transient torsional vibration, which is associated with the dynamic torque on the shaft, used the surface of the shaft encoding, as described above, according to one variant embodiment of the invention. Dynamic torque is determined by the phase shift of the signature encoding in the time domain, whereas the torsional vibration generates high-frequency harmonic components in the frequency domain, which are integral with the main natural frequency of vibration of the shaft, as shown in Fig, which presents a multi-point signal dynamic torsional vibration based on the reflections in the time domain according to one variant embodiment of the invention; and Fig, which presents multipoint range of dynamic torsional vibration based on the reflection from the probe according to one variant embodiment of the invention. Large bandwidth achievable using the techniques described herein vibration measurements in the frequency domain, allows to identify the above fashion vibration power spectra and phase.

Described herein the principles of vibration measurements can be implemented to provide simultaneous monitoring of the phenomena of permanent and transient Flexural and torsional vibrations of the main natural frequency of rotation of the shaft in the Garm the technical components of higher orders, as specified above. In particular, transient nonlinear torsion fashion, which correspond to periods of tension with relatively high amplitudes, it is possible to identify immediate and short-period high-frequency oscillations, which can be used to identify the transition of the defect transmission lines. Such automated monitoring technique can be applied, for example, on the steps of the different pressure steam turbine, including, without limitation, megalocornea, or shafts for power plants, where the shaft breakage can be caused by transition and nonlinear Flexural and torsional vibration.

Described herein the principles of multiplexing multiparameter detection of torsional vibration on the basis of a bundle of fibers, although useful for diagnosing failures of the rotor or shaft, is also useful for the simultaneous measurement of mechanical deformation of the shaft under the action of heat and transient changes in the speed of rotation of the shaft, and transient non-linear characteristics of the vibration.

The advantages provided by the measurement system vibration having the described characteristics include, without limitation:

1) fiber-optic monitoring system vibration shaft turbomachine system insensitive to electromagnetic interference;

2) the system can be equipped with the performance in harsh environmental conditions due to temperature, pressure, humidity, etc.;

3) the system simultaneously provides multiple modes of vibration (lateral, bending and torsion) by measuring dynamic reflection or from the surface of the shaft with optical encoding, or from the bare surface of the shaft;

4) the system has no moving parts and has no requirements for optical alignment;

5) the system detects dynamic signals reflected from the surface of the shaft using an optical(them) of the divider(s) on the basis of a bundle of fibers, for example, optical(them) of the divider(s) 1x2, 1x4 and 1x8, which allows the simultaneous multi-point measurement of vibration using a single tool;

6) fiber-optic measuring system uses a probe to measure the reflection built using tubes made of metal with high melting point, low thermal expansion, resistant to oxidation (i.e Kovar, Invar, Inconel or Incoloy etc); high-temperature metal adhesive as a binder material; one fiber for delivering the beam of incident light (i.e. laser), and multiple (ie 6) fibers with hexagonal configuration for receiving dynamic signal reflection according to one variant of implementation;

7) the system is configured so that the received signal reflecting the value can be passed on photodetector matrix optical probe reflection (i.e. optical coupler 1x2, 1x4 or 1x8), which is Packed in the cable in steel corrugated sheath according to one variant of implementation;

8) the use of a measuring probe, which is insensitive to temperature, because the reflected signal transmitted via the optical fiber, is limited to a narrow spectral range with high wavelength cutoff of less than 2 μm, which makes it insensitive to large radiation wavelength; and also the fluctuation of the reflection induced by thermal radiation is negligible when T<1200°F;

9) use of the probe, the surface of which is coated with a thin film of hydrophobic high-temperature ceramics based on aluminum oxide according to one variant of implementation, so the amplitude of the dynamic signal reflection does not depend on humidity;

10) the use of fiber-optic probes arranged in a matrix, allows to distribute a single source of light on a large number of individual probes, providing higher spatial resolution of the measurement, which is ideal for applications multipoint measurement, for example, for monitoring vibration of the shaft of the steam turbine from the high pressure stage to the low pressure stage;

11) using the light source is multiple wavelengths, in order for the dynamic measurement of the reflected signal was insensitive to the optical absorption due to the humidity, mineral oil and dirt, by differentiation of the measurement reflection at the same time for different wavelengths;

12) the use of signal processing dimension, which includes filtering technology, which allows you to recover the envelope of the noise and the carrier to ensure the cross-correlation function to provide operational analysis and monitoring of static and dynamic state of vibration;

13) the method of predictive diagnostics and forecasting on the basis of the analysis of nonlinear transient vibration; and

14) using the practical method of monitoring the alignment of the bearings, rotor and shaft are measured by simultaneous observations of the amplitudes and modes of nonlinear vibration.

Although there is illustrated and described are only some of the features of the invention, the specialists in this field of technology can offer numerous modifications and changes. Therefore, it should be understood that the invention is intended to cover all such modifications and changes, the essence of the invention.

The list of items

10 Fiber-optic system

measurement of torque

12 Multicolor source of the IR lighting

14 the Area of the surface of the shaft

16 the Area of the surface of the shaft

18 the Area of the surface of the shaft

20 the Area of the surface of the shaft

22 the Divider on the basis of extensive beam fiber

24 the Surface of the shaft of the turbomachine

26 probe reflection

28 Probe reflection

30 Probe reflection

32 Probe reflection

34 Matrix of photosensitive detectors

36 Block signal processing

38 the encoding Mechanism of the shaft surface

40 Angular displacement

42 Branched beam of fibers

44 Branched beam of fibers

48 the Original time signal

50 signal with a time delay

64 Block cross-correlation

66 Block low pass filter

68 Block FFT

70 encoding Scheme and signal processing

72 Unit updated estimates of the phase shift

74 the evaluation Unit of the phase shift high precision

76 Block a rough estimate of the phase shift

80 the Set of source signals

82 signals with a time delay due to torque

90 the Divider on the basis of extensive beam fiber

92 Optical fiber

94 Probe transmission

100 Probe reflection

102 Central fiber

104 Coaxial fiber

106 Working distance

108 working point working distance

110 working point working distance

112 Wedge-shaped grooves

114 Rectilinear grooves

120 the Template code is the formation of surface V-grooves

122 Template encoding multiple periodic lines

124 coding Pattern with a straight line

130 measurement Signal of the torque from the shaft surface, encoded by a straight line

132 the measuring Signal of the torque from the shaft surface, the coded V-grooves

134 detection Signal dynamic torque on the basis of the time delay

140 Reflected signal from the surface of the shaft encoded periodic or frequency-modulated by straight lines

142 Surface of the shaft, encoded periodic lines

200 Fiber-optic instruments measure the torque and vibration for Turbomachinery system

202 steam turbine

204 Generator

206 Power reducer

208 Gas turbine

210 Fiber optic monitoring system vibration

212 steam turbine

214 Branched fiber bundles

216 the shaft Surface with optical encoding

220 Laser light signals

218 Matrix of photodetectors

224 Multiple reflected signals

226 Optical beam divider fibers

230 Matrix of photodetectors

1. The way to measure static and dynamic torque, modes of vibration and the corresponding operating state of the shaft turbomachine system containing phases in which
transmit the light of the single light source in a variety of locations on the surface of the shaft turbomachine system through many bundles of optical fibers, moreover, many locations on the surface of the shaft is located in a substantially axial direction between the ends of the at least one shaft, so that many dynamic reflected light signals received from multiple locations on the surface of the shaft at least one high-temperature probe reflection on the basis of a bundle of fibers, while at least one shaft rotates, at least one of the many places on the surface of the shaft has a modified texture, a certain wedge-shaped groove, deposited on the surface of the shaft, by changing the depth of the surface in the desired areas of the surface of the shaft relative to other areas of the surface of the shaft, and at least one more from a variety of locations on the surface of the shaft includes a modified texture, and the depth of the wedge-shaped groove provides a signal front the working point and the signal of the rear operating point so that the corresponding time delay can be found from either of two locations wedge-shaped grooves to determine the value of the angle of torsion of the shaft by a differential characteristics of the pattern of reflection during each cycle of rotation; and
determine at least one characteristic of the torque shaft turbomachine system based the and at least one dynamic characteristic of the reflected light signals, received from at least one of the locations on the surface of the shaft;
determine at least one characteristic of the vibration shaft turbomachine system based on at least one dynamic characteristic of the reflected light signals received from at least one other location on the surface of the shaft.

2. The method according to claim 1, in which each optical fiber is branched so that the light transmitted to each of the locations on the surface of the shaft turbomachine system through a single tap of the branched optical fiber splitter and forth, so that the light received from each location on the surface of the shaft in response to transmitted light is received through the probe reflection bi-branched optical fibers.

3. The method according to claim 1, in which the transmission of light at many locations on the surface of the shaft turbomachine system includes the transmission of light in optically encoded shaft surface turbomachine system.

4. The method according to claim 3, in which determining at least one characteristic of a torque or vibration of the shaft turbomachine system based on at least one dynamic characteristic of the reflected light signals, includes:
determine the value of the angle of torsion of the shaft, based on sets the characteristics of the reflected signal; and
the defining characteristics of the torque shaft turbomachine system, based on the value of the angle of torsion of the shaft, corresponding to a time delay or phase shift by differentiation of any two characteristics of reflection.

5. The method according to claim 4, in which determining the value of the angle of torsion of the shaft, based on the set of reflected signals, includes:
measurement by means of photodetection, when the difference between the characteristics of the pattern of reflection of the reflected light signals detected by multiple probes reflections on the desired desired wavelength exceeds a desired threshold value;
determination of the differential time delays associated with the reflected signal; and
determine the value of the angle of torsion of the shaft, based on the reflected signal differential time delays from their recognition of patterns of reflection.

6. The method according to claim 4, in which the determination of the torque shaft turbomachine system, based on the value of the angle of torsion of the shaft, contains the calibration of torque sensors for use with the corresponding shaft turbomachine system so that the value of the twisting angle corresponds to the absolute value of the torque obtained from reference tables, or formulas, Il the calibration of the transfer function.

7. The method according to claim 4, in which the determination of the torque shaft turbomachine system, based on the value of the angle of torsion of the shaft, contains the calculated torque value based on the value of the twisting angle.

8. The method according to claim 7, in which the determination of the torque shaft turbomachine system, based on the value of the angle of torsion of the shaft, also contains a calibration of any difference between the reflected signals taken from different locations along the at least one shaft turbomachine system so that there is no measurable difference between the measured signals associated with the optical fiber, when at least one shaft is stationary, and to calculate the torque values.

9. The method according to claim 3, in which the defining characteristics of torque or vibration of the shaft turbomachine system based on at least one characteristic of the reflected signals, includes:
determining the fundamental frequency of vibration of the shaft turbomachine system and the desired number of vibration frequencies of the higher order harmonics of the shaft turbomachine system based on the set of received reflected signals; and
determination of the torsional vibration of the shaft turbomachine system based on the fundamental frequency of vibration of the shaft and the frequencies of the harmonics of a higher order vibration mode in the La.

10. The method according to claim 1, wherein determining characteristics of the torque or vibration of the shaft turbomachine system based on at least one characteristic of the reflected signals, includes:
determining the fundamental frequency of vibration of the shaft turbomachine system and the desired number of frequencies of vibration modes of higher order harmonics of the shaft turbomachine system based on the set of received reflected signals; and
determination of Flexural vibration of the shaft turbomachine system based on the fundamental frequency of vibration of the shaft and the frequencies of the harmonics of a higher order vibration mode of the shaft.

11. The method according to claim 1, in which the transmission of light in a variety of locations on the surface of the shaft turbomachine system through many bundles of optical fibers, and a lot of locations on the surface of the shaft are located in a substantially axial direction between the ends of the at least one shaft turbomachine system so that the number of light signals reflected from multiple locations, while rotating at least one of the shaft that contains the transmission of light through the element branched beam of fibers and receiving the reflected light through the element bi-branched tuft of fibers, each bundle of optical fibers associated with the location of the shaft, is connected with the corresponding probe on the expression, located in the immediate vicinity of the surface of at least one turbomachine shaft.

12. The method according to claim 1, in which the transmission of light in a variety of locations on the surface of the shaft turbomachine system through many bundles of optical fibers, and a lot of locations on the surface of the shaft are located in a substantially axial direction between the ends of at least one turbomachine shaft so that the number of light signals are taken from a variety of locations during the rotation of at least one shaft includes transmitting light from a light source selected from a light source operating at a specific wavelength LED light source, a broadband light source and multichromatic light source employed or in continuous mode, or in the frequency modulated pulse mode.

13. System for measurement of static and dynamic torque, modes of vibration and the corresponding operating state of the shaft turbomachine system containing:
the only light source configured to transmit light to the surface of at least one shaft turbomachine system through many bundles of optical fibers arranged in a multitude of locations near the surface of the at least one shaft, and sets the locations together are in a substantially axial direction between the ends of the at least one shaft;
at least one high-temperature probe reflection on the basis of a bundle of fibers configured to detect dynamic light reflected from the surface of the at least one shaft turbomachine system in response to transmitted light during rotation of at least one shaft turbomachine system and to generate dynamic reflected light signals;
the measurement mechanism configured to determine the torque or vibration on at least one shaft turbomachine system in response to the dynamic characteristics of the reflected light signal or pattern recognition on the basis of the signal processing in the time domain and in the frequency domain, while
Turbomachinery shaft provides a mechanism for encoding performed by the modified texture defined by V-grooves, deposited on the surface of the shaft, by changing the depth of the surface in the desired areas of the surface of the shaft relative to other areas of the surface of the shaft at at least one location of at least one of the shaft near the corresponding location of a bundle of fibers, but not all locations at least one of the shaft near the locations of a bunch of fibers, while the depth of the wedge-shaped groove provides a signal front the operating point and the signal of the rear operating point thus the corresponding time delay can be found from either of two locations wedge-shaped grooves to determine the value of the angle of torsion of the shaft by a differential characteristics of the pattern of reflection during each cycle of rotation.

14. The system of item 13, in which at least one shaft turbomachine system has an optical encoding.

15. System 14, in which the vibration is a torsional vibration.

16. System 14, which shaft with optical encoding contains the optical encoding mechanism attached to the shaft surface or embedded in it by laser micromachining processing, laser marking or welding.

17. System 14, which shaft with optical encoding contains the mechanism of optical encoding is designed so that the optical encoding reduces the detection signal of the rejection regions of the shaft surface contaminated with rust or dirt.

18. The system of item 13, in which the vibration is a bending vibration.

19. The system of item 13, in which each optical fiber transmission line includes an extensive bundle of fibers selected from plastic fibers, quartz fibers, sapphire fibers.

20. The system of item 13, further containing a probe reflection 1×2 or 1×N, corresponding to each optical ox the KNU, each probe reflection configured to transmit light received from the light source by its corresponding optical beam of fibers to the surface of at least one of the shaft through the allocation transfer probe reflection and additionally configured to receive light reflected from the surface of the at least one shaft through the outlet of the measuring probe reflection.

21. The system of item 13, in which the measurement mechanism includes a torque sensor for use with a corresponding at least one shaft turbomachine system, thanks to which the measured value of the twisting angle of the shaft corresponds to the absolute value of the torque extracted from the information table, or formula, or from a calibration transfer function.

22. The system according to claim 1, in which the measurement mechanism includes a signal processor configured to determine, when the characteristics of the received reflection light at the desired wavelength exceeds the desired threshold, determining differential time delays associated with characteristics of the reflected signal, determine the value of the twisting angle of the shaft based on the differential time delay of the reflected signal and determining the torque on the shaft on the basis of the twisting angle of the shaft.

23. The system according to item 22, in which the processor C the signals from the pattern recognition signal reflection is also configured to calibrate any differences between the desired reflected signals to reduce unwanted measurable difference between the desired reflected signals.



 

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The invention relates to apparatus for determining the damage on the ship, for example, the hull of the vessel containing the distributed optical fiber located near the hull, and these optical fibers are attached to the Central unit, suited for the characterization of optical fibers on the mode of transmission of light to determine the damage to the hull

FIELD: measuring equipment.

SUBSTANCE: invention belongs to fibre-optical sensors and can be used for check and measurement of parameters of voltage. The fibre-optical sensor of spiral structure is the multi-turn spiral element created by a spring wire. The set of a teeth of deformation is continuously distributed on the top surface and the bottom surface of a spring wire in the longitudinal direction along a spring wire; in two adjacent turns of the spring wire the deformation teeth on the bottom surface of the top turn of the spring wire and deformation teeth on the top surface of the bottom turn of the spring wire are arranged in staggered order to each other. An alarm optical fibre is clamped between deformation teeth on the bottom surface of the top wire of the spring wire and deformation teeth on the top surface of the bottom turn of the spring wire and is connected to the test facility by the optical fibre of transfer.

EFFECT: increase of accuracy of measurement.

10 cl, 10 dwg

FIELD: measuring equipment.

SUBSTANCE: invention belongs to area of instrumentation and can be used for creation of distributive systems of measurement of temperature and deformation. The Brillouin system for tracking of temperature and deformation contains one - or bilateral fibre with a set of fibre Bragg gratings (FBG) on different lengths of waves and a laser system with the setting excitation, adjusted in a range essentially bigger, than Brillouin shift. FBG are distributed along the length of the placed fibre and serve as chosen reflectors of length of the wave, allowing to support operation of the device even in case of a rupture of fibre.

EFFECT: increase of accuracy and reliability of these measurements.

7 cl, 4 dwg

FIELD: electricity.

SUBSTANCE: invention is referred to electric cable with in-built strain-gage fit specifically to measure static and dynamic deformations, in particular, bending strain. Method of bending strain control for electric cable includes stages of the cable equipment with peripheral and mechanically unsymmetrical bearing element having higher resistance to tensile loads than to compression ones and with fibre-optical sensor.

EFFECT: invention provides for high duty cables, in particular, in mobile units, controllability and traceability of bending strain area.

9 cl, 15 dwg

FIELD: electricity.

SUBSTANCE: electric cable with strain-gage located longitudinally along the cable and containing strain-gage optical fibre installed in flexible neutral area that surrounds and includes flexible neutral longitudinal axis of the electric cable, and at least two longitudinal structural elements where at least one of at least two longitudinal structural elements represent a core containing electric conductor with strain-gage in-built into filler resistant to strain; it connects at least one of at least two longitudinal structural elements with strain-gage. By means of open cable structure strain endured by at least one of at least two longitudinal structural elements can be transmitted to strain-gage at least in stretched state. In preferred variants of implementation the electric cable represents high-duty cable. Invention is also related to control method of strain and, preferably, temperature of electric cable.

EFFECT: invention is oriented to creation of deformation control system to measure at least stretching strain for several electrical cables and, in particular, several high-duty cables.

30 cl, 12 dwg

FIELD: process engineering.

SUBSTANCE: glass fibre is introduced in composition used for forming controlled object as a material similar to that used as a filler for forming part carcass matrix, that glass fibre allows channeling light beam there through. Note here that glass fibre intact lengths, longer than said part, are used to be arranged to cross paths of probable defect development in part sections not subjected to processing. Occurrence of defect is detected by light beam passage or decreased in emergent light flux brightness.

EFFECT: efficient detection of defects.

6 cl, 1 dwg

FIELD: physics.

SUBSTANCE: optical fibre structure with Bragg lattices is put into composite material during production thereof. The spectral position of peaks of the Bragg lattices is measured after making the structure from the composite material and distribution of mechanical and thermal deformations inside the structure of the composite material is determined by solving the system of equations: , where f(T,ε) is the distribution function of mechanical and thermal deformations on the structure made from composite material (T is the temperature value, ε is the deformation value); f(Ex, y, z) is the distribution function of elastic properties of the structure made form composite material, Ex, y, z is the Young 's modulus tensor; f(αx, y, z, vx, y, z) is the distribution function of thermal characteristics of the composite material (αx, y, z is the coefficient of volume expansion tensor, vx, y, z is the thermal conductivity coefficient tensor);f(Fload, FT) is the distribution of mechanical and temperature effects on the structure made from composite material (Fload is the value of the mechanical effect, FT is the value of the temperature effect); fFBG(T,ε) is the function of total deformation on the path of the optical fibre with Bragg lattices (T is the temperature value, ε is the deformation value); fi-FBG(Δλ) is shift transformation function of the position of the i-th peak of the Bragg lattice to the temperature value and deformation (Δλ is the displacement of the peak of the Bragg lattice). The optical fibre contains two or more Bragg lattices which are not more than 5 mm long. The distance between the Bragg lattices and one optical fibre is not less than 5 mm.

EFFECT: high measurement accuracy.

3 cl, 15 dwg

FIELD: physics.

SUBSTANCE: proposed transducer comprises load secured on controlled element and strain-gage transducer to convert voltage across stress-optical element into electric signal, and signal processing unit. Load is made up of plate to concentrate strain at stress-optical element. Stress-optical element is fixed in said plate as-stressed so that initial stress force acts in two mutually perpendicular directions. Note that stress-optical element is fixed at plate thinned center by means of Morse taper. Note also that, additionally, two mutually perpendicular through cuts are made not corrupting plate integrity, cuts axes being directed at 45° to loads axis. Cuts axes are aligned with that of taper hole for stress-optical element attachment.

EFFECT: higher sensitivity, thermal compensation.

5 cl, 1 dwg

FIELD: measurement technology.

SUBSTANCE: declared invention refers to the measurement of the stress of wall in hollow product. Method of determination of circumferential stress of wall in the hollow product is based on the polarization optical method. When implementing the method the hollow product located in immersion liquid is X-rayed with polarized light. The analysis made of the image of double refraction of polarised light rays from their passing through the mentioned product. Upon the results of the analysis the circumferential stresses in the mentioned product is determined. When determining the circumferential stresses the Y-raying of the hollow product located in the immersion liquid with polarised light is realised from inside of the hollow product, and the analysis of the watched image of double refraction of polarised light rays is made from the their passing through one of the diametrically opposite parts of the mentioned product's wall.

EFFECT: improvement of the measurement accuracy, simplification of construction and expansion of the features.

2 cl, 1 dwg, 1 ex

FIELD: physics; measurement.

SUBSTANCE: present invention relates to a device and method of determining a force vector and can be used in a touch sensor of a robot arm. The optical touch sensor has a sensitive part and photographic unit. The sensitive part comprises a transparent flexible case and several groups of markers, placed inside the flexible case. Each group of markers contains several coloured markers and the markers, which make up different groups, have a different colour in each group. The flexible case has an arbitrary curved surface. Behaviour of the coloured markers when an object touches the curved surface of the flexible case is interpreted as information about the markers in form of an image using the photographic unit. The sensor also has a device for reproducing force vector distribution, meant for reproducing the force applied to the surface, based on information on the behaviour of markers, which is obtained based on the given information on markers in form of an image.

EFFECT: design of an optical touch sensor with an arbitrary curved surface, which allows for measuring three-dimensional distribution of a force vector, which can be used as a touch sensor for a manipulator (robot arm).

26 cl, 13 dwg

FIELD: physics, measuring.

SUBSTANCE: invention concerns the electronic technics, in particular, to microelectronics, and can be used at manufacturing of IS crystals and discrete semiconductor devices. The essence of declared expedient of the control of mechanical voltages in structure film - substrate consists in formation between a film and a substrate of the intermediate stratum which is selectively etched through windows in a film of the round shape with formation in a backlash film - substrate of the interference figure reflecting quantity and a direction of a vector of mechanical voltages.

EFFECT: expansion of technical possibilities of method at expense of possibility of control of direction of vector of mechanical voltages.

4 dwg

FIELD: measurement equipment.

SUBSTANCE: method to measure amplitude of nanovibrations ξ, consists in the fact that an object is illuminated with laser radiation, they convert radiation reflected from it into an electric (autodyne) signal, the signal is decomposed into a spectral row, and they measure the value of amplitude of the harmonic Sx at the frequency of object oscillation Ω. At the same time additional mechanical vibrations are imposed onto the object at the frequency Ω1 with minimum amplitude, they measure the maximum value of the harmonic S1max, at the frequency Ω1 as the amplitude of additional mechanical oscillations increases, they increase the amplitude of additional mechanical oscillations until there are interference maxima and minima appear on the autodyne signal on the dedicated interval of time between points that correspond to extreme positions of object displacement, they calculate the ratio of time of decay tdec of the autodyne signal to the time of its increase tinc in the dedicated interval of time. In the case when the value tdec/tinc is more than 1, they calculate tinc/tdec, on the basis of the dependence tdec/tinc(C) or tinc/tdec(C) they determine the level of the external optical feedback C, they calculate Sx/S1max, according to the dependence S1/S1max(ξ, S) with the previously determined C they find ξ.

EFFECT: higher accuracy of measurement of amplitudes of nanovibrations.

17 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: apparatus includes a laser, a divider, first and second lenses and series-connected ultrasound generator and piezoceramic radiator, located in a container in which an analysed sample and a converging acoustic lens are placed on one line with the radiator. The wall of the container is optically reflecting in the direction of the sample from the radiator. The container is sealed and filled with an inert gas under pressure, which ensures minimal re-reflections at the sample and gas media boundaries. The optically reflecting surface is made of two optically transparent thin and durable walls, with a thin layer of mercury in between. When recording an acoustic image, the laser operates in waiting pulse mode. One of the laser beams split by the divider is collimated by a first lens and then, through reflection from the optically reflecting elastic surface of the container, falls on a holographic plate, and the second beam is collimated by a second lens and falls on the same surface of the holographic plate, forming a holographic interferogram.

EFFECT: high resolution of the device, high noise-immunity thereof and easy control.

1 dwg

FIELD: measurement equipment.

SUBSTANCE: remote vibration sensor includes am emission source, a two-element photoreceiver and a subtracting unit, the inputs of which are connected to outputs of the photoreceiver elements. In addition, remote vibration sensor includes an optic focusing system located in front of the emission source and providing minimisation of cross dimensions of the reflected beam at a receiving point.

EFFECT: increasing sensitivity and range of coverage of equipment for detection and monitoring of vibrations of objects.

2 dwg

FIELD: physics.

SUBSTANCE: piezoelectric detector with a point contact measures the amplitude of vibration and distribution thereof on radiating transition surfaces, compares said amplitude with the amplitude of vibration of the end surface while applying, across the piezoelectric transducer of the vibrating system, a voltage which does not exceed 0.1 times the operating voltage when exciting vibrations in air; the vibrating system is immersed in treated liquid such that the radiating end surface is not covered by the liquid; operating voltage is applied across the piezoelectric transducer of the system; amplitude of vibration of the end surface of the radiator is measured, while observing an enlarged image of light flux overlapped by the vibrating end surface and using the results of comparing amplitude of vibrations obtained by the piezoelectric detector with a point contact, the amplitude of vibration of the radiating transition surfaces and distribution thereof in the treated liquid are established.

EFFECT: enabling measurement of the amplitude of vibration of an ultrasonic transducer in process media during operation of a radiator.

3 dwg

FIELD: measurement equipment.

SUBSTANCE: registration system comprises a fibre-optic metering line on a single-mode optical fibre with an installed Fresnel or Faraday reflector at one side, and at the other side - connected to an optoelectronic unit, which comprises a laser source connected with the first input of a splitter of X-type. The first output of the splitter is connected to the specified metering line, and the second one - to a sound-insulated coil from a single-mode fibre, serially connected to a reflector on the second end. Lines produce an open double-arm circuit of a fibre Michelson interferometer, signals from which arrive from the second input/output of the splitter to a photodetector and a recorder of vibroacoustic signals. Local sensors of vibration signals are linear sections of fibre in the metering line, fixed to the vibrating surface of the object, and sensors of acoustic signals are represented by a single small-sized coil from a single-mode optical fibre or at least one multiturn element from a single-mode optical fibre.

EFFECT: increased sensitivity of measurements in a wide band of frequencies of both vibratory and acoustic signals with the help of one fibre-optic line.

11 cl, 1 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to controlling and measuring equipment and may be used to produce data on structure of acoustic fields in development of acousto-electronic devices, for registration of acoustic fields during physical research of wave processes in acoustics, to control structures in objects, which are not transparent for visible light. Substance; the device comprises an acousto-optical Bragg cell, a source of coherent optical radiation, optical systems for generation of a light beam falling onto a Bragg cell and processing of a light beam diffracted in the cell, and also a device for registration of an object image. The acousto-optical Bragg cell is formed by serially acoustically joined first and second acoustic lines with various values of acoustic waves propagation speed. End coupled surfaces of acoustic lines have a spherical shape of identical radius with a centre of curvature arranged on the longitudinal axis of acoustic lines. At the same time whenever the speed of propagation of an acoustic wave in the first acoustic line is more than the speed of propagation of the acoustic wave in the second acoustic line, the spherical surface of the first acoustic line is arranged as concave, and of the second acoustic line - as convex. And vice versa, if the speed of propagation of an acoustic wave in the first acoustic line is less than the speed of propagation of the acoustic wave in the second acoustic line, the spherical surface of the first acoustic line is arranged as convex, and of the second acoustic line - as concave. The acousto-optical interaction is carried out in the second acoustic line, and the investigated acoustic object is arranged on the flat end surface of the first acoustic line.

EFFECT: production of a bright stigmatic image during visualisation of acoustic fields from microobjects.

2 cl, 5 dwg

FIELD: physics.

SUBSTANCE: in the method, the emitter used is a helium-neon active element which is optimised to obtain laser radiation at wavelength 3.39 mcm and placed in a semiconfocal cavity with two reflecting surfaces. The radius of curvature of the concave mirror is comparable with double the length of the active element. The analysed surface is used as the second reflecting surface of the cavity. The axis of the cavity is adjusted perpendicular to the analysed surface until generation occurs and maximum value thereof is obtained. The length of the cavity is readjusted during scanning of a spherical mirror within the wavelength and the value of output laser power is measured. The length of the cavity is adjusted on the linear part of the curve of laser power versus the length of the cavity and the variable component of laser power, proportional to surface vibrations, is measured. The variable component of the photodetector is analysed and the amplitude and frequency of vibrations of the analysed surface are determined via Fourier or wavelet transform.

EFFECT: wider frequency range of measured amplitude values of nanovibrations and enabling contactless measurement of absolute dynamic displacements of the probed surface with micron spatial resolution.

2 dwg

FIELD: physics.

SUBSTANCE: additional membrane which reflects sound waves is placed on the propagation path of sound waves, where dimensions of said membrane are not smaller than the wavelength in the lower ultrasonic frequency range of the controlled devices, and said membrane is moved towards or opposite the direction of propagation of the vibrations, and standing wave pressure picked up by the additional membrane is transmitted to a microphone diaphragm which converts the pressure into an electric signal, presence of which indicates presence of acoustic vibrations.

EFFECT: simplification, wider field of use of the method and wider range of detected frequencies.

1 dwg

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