The muffler

 

(57) Abstract:

The muffler is designed to reduce noise, mainly in gas turbines. The muffler includes a housing with inlet and outlet openings located in the housing along a flowing path of the sound-absorbing elements having a corrugated shell, filled with sound-absorbing material, while the sound-absorbing elements in the form of cylinders with conical caps, fixed vertices on the diaphragm, which is placed in the input and output holes of the housing, with one side of the attachment points of the conical caps with aperture are telescopically mounted parts. Effect: increased reliability. 2 Il.

The invention relates to the design of turbomachines, in particular, to the design of devices to reduce noise in the exhaust path of the gas turbine installation.

Known cellular muffler (and.with. 1815387, F 02 To 1/34), comprising a housing located in the housing package perforated plate members forming parallel channels, which are placed in the fibrous absorbent material.

Known muffler has a number of design and operational glashauser sections with the case when thermal expansion of the element causes the dynamic loads on the structure, which in turn cause deformation of the inner shell.

An object of the invention is to increase the effectiveness of noise control, reliability, and manufacturability of the design.

The technical result is achieved by the fact that the silencer of a gas turbine, comprising a housing with inlet and outlet openings located in the housing along a flowing path of the sound-absorbing elements having a corrugated shell, filled with sound absorbing material, sound-absorbing elements in the form of cylinders with conical caps, fixed vertices on the diaphragm, which is placed in the input and output holes of the housing, with one side of the attachment points of the conical caps with aperture are telescopically parts installed.

The aperture is made in the form of lattices of rods streamlined cross-section. The body of the muffler is a structure of power in the form of the spatial structure of the square tubes, the outside is faced with sheets of steel, and the inner side perforated sheets, the volume between the inner and outer walls is filled with absorbent material.

Kosterina, having a minimum cross-section, allows to reduce the hydraulic resistance of the gas path, which leads to increased system efficiency. In the flow of hot gases cylindrical elements expand, but due to the fact that the attachment is made in the form of telescopically installed items, expansion occurs without causing dynamic loads on the structure and, accordingly, deformation of the inner shell. Filling the internal volume of the body of the muffler sound-absorbing material leads to an additional reduction of the noise level.

In Fig. 1 shows the proposed muffler.

In Fig. 2 shows a cross-section telescopic fastening.

The proposed muffler includes a housing 1 and placed in it the package sound-absorbing elements 2. Each section is a cylinder 3 of the perforated sheet with lids 4 in the form of truncated cones. Within the sections is sound-absorbing material 5. Sections are fastened by screws 6 to the diaphragm 7 from the inlet holes and the rods 8, mounted in the sleeve 9, the diaphragm 10 from the side of the outlet. The body of the muffler is a main frame made of square tubes, with Eanna and outer walls is filled with sound-absorbing material 5.

The silencer works as follows. Sound waves are propagated from the noise source (in this case from the blades of an axial compressor GTU) in the exhaust tract and entering the free space of the muffler, cause oscillatory movement of the air in the pores of the absorbent material. Due to the viscous friction of the gas in the pores of the absorbent material oscillatory motion of the air is converted into thermal energy, resulting in lower noise.

By reducing the dynamic loads on structural elements caused by thermal expansion of structural materials, increases the reliability of the design, due to maximum use of the internal volume of the silencer for placement of sound-absorbing material increases the efficiency of absorption, but due to the streamlined shape of the sound-absorbing elements and streamlined cross-section of the diaphragm is reduced hydraulic resistance of the gas path.

The muffler predominantly gas-turbine plant, comprising a housing with inlet and outlet openings located in the housing along a flowing path of the sound-absorbing elements having a corrugated shell, filled with sound-absorbing the AMI, fixed vertices on the diaphragm, which is placed in the input and output holes of the housing, with one side of the attachment points of the conical caps with aperture are telescopically mounted parts.

 

Same patents:

The invention relates to aircraft engine, in particular to devices for muffling the noise of a jet turbine engine

The invention relates to aviation, particularly to nozzles for aircraft engines

The invention relates to the field of aircraft engine industry, and specifically to methods and devices for reducing noise of jet engines

FIELD: mechanical engineering; gas-turbine engines.

SUBSTANCE: proposed method includes delivery of working medium, for instance, liquid or gas, to limited exhaust zone of exhaust jet at angle to its axis. Jet of working medium is preliminarily delivered at different angles to axis of exhaust jet which are successively changed and noise level is measured corresponding to each said angle, and angle is chosen at which noise level is minimum, and delivery of jet of working medium is further provided at said angle.

EFFECT: improved efficiency of noise damping of exhaust jet, reduced relative consumption of working medium per each decibel of noise damping.

3 cl, 1 dwg

FIELD: aircraft engineering.

SUBSTANCE: invention relates to device aimed at reduction of noise of gas-turbine engines. Proposed mixer of bypass turbojet engine contains nozzle, shroud and channels to pass gas and air of inner and outer loops located after shroud. Output edges of shroud are made in form of herringbones. Channels are formed by herringbones and two rows of alternating partitions, some of which being flat arranged in planes passing through axis of engine, and others are bent. Output edges of bent partitions lie in plane of flat partitions lower than flat partitions in direction of gas flow. Channel to pass air of outer loop is formed by herringbones, partitions and inner surface of nozzle. Channel to pass gas is formed by herringbones and partitions. Invention provides reduction of noise of bypass turbojet engine owing to multiple reflection of sound waves from mixer members and inner surface of nozzle and intensification of mixing of flows of inner and outer loops of engine.

EFFECT: reduced noises.

2 cl, 5 dwg

Noise suppressor // 2303151

FIELD: mechanical engineering; engines.

SUBSTANCE: invention can find wide application in double-flow turbojet engines for suspension of noise of exhaust streams. Proposed noise absorbing device includes fairing, channels of inner and outer loops, nozzle with cylindrical branch pipes and hollow pylons. Cylindrical branch pipes of nozzle are provided with outer ring spaces, and pylons connect ring spaces with outer loop channel. Envelope of fairing is made porous, being filled up with noise-absorbing material based on alumino-containing alloys, density 0.5-0.9 kg/cu.m, compression strength of 5-10 MPa and bending strength of 10-20 MPa.

EFFECT: improved reliability of device and efficiency of noise suppression.

1 dwg

FIELD: gas-turbine engines.

SUBSTANCE: invention relates to reaction nozzles with noise-damping devices. Proposed nozzle contains outlet pipe on outlet end face of which great number of adjacent herringbones is fitted, said herringbones being made detachable, in form of separate parts with fastening to outer or inner surfaces of outlet pipe or with alternation to both surfaces of outlet pipe with possibility of replacement. Herringbones are provided, each, with at least one divider in form of plates flat in longitudinal section.

EFFECT: increased service life and repairability of nozzle and efficiency of noise damping of reaction jet.

2 dwg

FIELD: methods for protection of the launch vehicle and its payload mainly from tie acoustic action of the rocket engine gaseous jet at a take-off.

SUBSTANCE: the method consists in formation of a hollows water curtain around the rocket engine gaseous jet after the exit of the rocket engine nozzle from the opening of the launching structure. Water may be supplied along the launch vehicle, in parallel with the rocket engine gaseous jet. The water curtain may have a closed shape, for example, a ring shape. Water is supplied preferably in the form of a series of flat water films.

EFFECT: reduced acoustic action on the launch vehicle and its payload due to reduced acoustic radiation of the rocket engine gaseous jet, as well as reduced gas-dynamic and heat loads on the system.

6 cl, 2 dwg

FIELD: device being a member of launchers of the launching complexes providing reduction of the acoustic action on the launch vehicle and cooling of the rocket engine gaseous jet at a take-off.

SUBSTANCE: the device has a closed-type water conduit with branch pipes and slots for water supply. The inner space of the water conduit is separated by a partition into two isolated chambers with individual branch pipes for water supply. The mentioned slots are made on the upper end surface of one of the chambers and on the lower end surface of the other chamber providing for formation of a hollow water curtain around the rocket engine gaseous jet. The water conduit may have a rectangular section and be installed on the bearing posts of the launching structure. In the preferable modification of the device the slots form a ring-shaped contour so that each subsequent slot overlaps the previous one at least by half-the length of the latter.

EFFECT: enhanced intensity of cooling of the rocket engine gaseous jet and reduction of the acoustic action on the launch vehicle and it payload.

4 cl, 3 dwg

FIELD: engines and pumps.

SUBSTANCE: aircraft turbojet engine comprises jet nozzle to eject gas jet stream or to combine two gas jet streams. Jet nozzle represents one or two outlet rings furnished with appliances to disturb one or both jet streams and are made up of at least one pair of channels to eject air jest at pressure. Aforesaid channels are open at jet nozzle outlet. Channels of each pair converge to form triangle of air jets interaction at their outlets. Note that the angle of channels convergence varies from 40 to 70, but preferably makes about 60.

EFFECT: reduced acoustic noise.

16 cl, 3 dwg

FIELD: engines and pumps.

SUBSTANCE: proposed aircraft engine comprises hollow nacelle, fan, gas turbine engine hot flow generator, fan channel inner fairing and multiple shutters. Fan channel inner fairing makes an external member of hot air generator to set, along with aforesaid nacelle, the boundaries of cold air channel and, with engine fairing, the boundaries of annular-section intermediate chamber. The latter has its rear section accommodating an appliance to allow communication of intermediate chamber with external side, nearby the boundary between cold and hot flows. Aforesaid shutters are fitted at the fairing rear to open only at gas turbine engine rpm higher than threshold value corresponding to at least aircraft cruising speed. Open shutters divert separate jets of hot air from hot flow into intermediate chamber, wherefrom hot air escapes via aforesaid communication aplliance.

EFFECT: reduced noise level.

15 cl, 23 dwg

FIELD: engines and pumps.

SUBSTANCE: mixer of variable cross-section flows for double-flow jet turbine engine of supersonic aircraft includes nozzle with centre on longitudinal axis of jet turbine engine, which is concentrically installed around gas generator. Nozzle includes multiple ambient air inlet holes made in its circumferential direction and opening to convergent zone of cold flow supplied from cold flow channel enveloping gas generator, with hot flow leaving the gas generator. Movable trays installed in holes are moving between two positions: between the first position in which they cover the nozzle holes and the second position in which they open the holes and are radially located in that position in the nozzle, thus providing ambient air inlet to convergent zone. Trays have azimuth constituent part of similar direction in order to put ambient air into rotary motion in convergent zone when the trays are in the second position.

EFFECT: inventions allow reducing noise of jet flow of jet turbine engine without increasing its overall dimensions.

5 cl, 7 dwg

FIELD: transport.

SUBSTANCE: invention relates to launching site equipment. Proposed method consists in creating closed water curtain adjoining carrier rocket aft section and to combustion product jet formed by incident jets pre-directed to carrier rocket axis at an angle. Incident flows of separate jets fall nearby said aft section with partial overlap. Proposed device comprises annular water duct arranged on launch pad, axially symmetric about rocket axis, with water feed branch pipes and channels to feed water on curtain made on water duct top face surface. Sleeve with through hole is secured in every aforesaid channel. Nozzle is secured on every said sleeve that deflect from vertical.

EFFECT: higher efficiency.

5 cl, 3 dwg

FIELD: the booth is assigned for ventilation of the shaft of the Metro.

SUBSTANCE: the booth includes an above the shaft building with air passing windows and an external barrier in the shape of a ring-type housing. The housing is fulfilled in the shape of a expanding upwards funnel with sound reflecting surface. A hollow gap is between the housing and the above the shaft building.

EFFECT: reduces noise levels with the aid of a single element out of sheet material.

1 dwg

Noise suppressor // 2338964

FIELD: physics; heating.

SUBSTANCE: suppressor is intended for decrease of aerodynamic noise in air ducts of mechanical ventilation and air conditioning systems. Suppressor contains the body in cavity of which there are mounted acoustic dissipation elements pairwise contacting at inlet, forming tapering air passage channels and provided with convex fairings in contact points, as well as swing-out mechanism consisting of levers and control rods rigidly mounted at end faces of acoustic dissipation elements by washers and cotters.

EFFECT: higher efficiency of noise suppression within all the operation modes of ventilation and air conditioning systems.

3 dwg

FIELD: machine building.

SUBSTANCE: suppressor is intended for reduction of hydrodynamic noise level emitted by liquid flow in pipelines. In closed cavity of hydrodynamic noise suppressor, pliable element is installed, for instance, hose, ends of which are connected to nipples withdrawn outside casing, pliable element is filled with air of pressure equal to maximum operating pressure of liquid, and free space of cavity is filled with loose or deformable substance, for instance, sand or rubber balls with diameter of up to 5 mm.

EFFECT: lower level of hydrodynamic noise level downwards hydrodynamic noise suppressor at all working modes by pressure, and also exclusion of necessity for adjustment and control.

2 cl, 1 dwg

FIELD: machine building.

SUBSTANCE: invention refers to procedure of noise suppressing. The noise suppressor consists of a case, of inlet and outlet branches and of a sound absorber. The sound absorber includes a rigid wall. A profiled layer out of sound absorbing material is attached to this wall. Sound absorbing material is produced by alteration of semi-sphere or partially spherical surfaces so, that between the wall and the layer of sound absorbing material there are continuous intervals alternating with air intervals formed with semi-sphere. The profiled layer is also attached to a perforated element of the case. This profiled layer consists of sound absorbing material obtained at alternation of semi-sphere or partially spherical surfaces. This arrangement facilitates alteration of continuous and air gaps formed with semi-sphere between the perforated element of the case with acoustic transparent material and the layer of sound absorbing material. Also the profiled layer at the rigid wall is a mirror reflection of the profiled layer at the perforated element of the case relative to symmetry line 0-0 of the solid profiled layer.

EFFECT: increased efficiency of noise suppressing.

3 dwg

FIELD: machine building.

SUBSTANCE: here is disclosed element of silencer consisting of case with flap cover. The case is filled with sound absorbing material placed in a protective shell. Walls of the case are formed with a sound absorbing structure made as cylinder perforated coaxial shells - internal and external ones. Between the shells there is installed a sound absorber made out of at least one profiled sheet. Also, profile of the sheet in cross section can be rectangular or trapezoidal.

EFFECT: improved acoustic characteristics in region of low, medium of high frequencies.

3 dwg

FIELD: machine building.

SUBSTANCE: device is designed for damping noise in flow through channels. The sound absorbing flow-through channel device forms at least two flow through channels having an inlet orifice and an outlet orifice. The flow-through channels at least partially are restricted with three walls dissipating acoustic energy; the walls are formed with a package of the first, second and third sheets forming flow-through channels between them. Each of the said first, second and third channels is equipped with at least one lug and/or recess. The said lug partially enters the recess, so that the outlet orifice of the flow-through channel can not be visualised through the inlet orifice and vice versa.

EFFECT: additional dissipation of sound energy.

17 cl, 20 dwg

Up!