The method for determining the center core of the vortex (vortex) and its location relative to the inlet
(57) Abstract:The invention relates to aircraft installations, in particular to methods for determining the vortex in front of the intakes. The method for determining the center core of the vortex (vortex) and its location relative to the water is that on the screen 9, which is located under the intake 7, placed imitators of foreign objects 11, create a vortex by suction of water through the intake and determine the location of the vortex center by measuring the distance from the top of the hill formed by the accumulation of imitators foreign objects 11 for sucking water up to the front lower edge of the intake 7 and from the top of the hill to the symmetry axis of the intake 7. The method allows to define the Central core of the vortex and its location relative to the intake with the determination of quantitative parameters of its location after conducting experimental research. 3 Il. The invention relates to aircraft installations, in particular to methods for determining the vortex (vortex) in front of the intakes.There is a method of determining the currents from the bulk to the surface of the water tracer particles in the form of aluminum powder, with the ith particle to specify fully and quantitatively the Central core of the vortex, as if they are on the water surface, then only display the flow around the vortex (vortex) or reaches the water surface, and immerse them in water is not possible due to the fact that they come with a small size. Basically they are applicable on the water surface.Closest to the invention is a method of determining the vortex (vortex) by bringing the water to the free surface of liquid (water), as this is because a sufficient intensity of the vortex (vortex) in its nucleus directs the air and makes it the core of visible without any coating  .The disadvantages of this method is the impossibility of determining the center core of the vortex in quantitative terms, especially regarding water, as on the free surface of the water are the components of velocity lying in its plane, and is "walking" of the vortex (vortex) relative to the intake. In addition, the Central core of the vortex (vortex) not measured for this reason, after conducting experimental research.The objective of the invention is to improve the accuracy of determination of the center core of the vortex (vortex) and its location relative to the intake.In Fig. 1 shows a diagram of the installation of Fig. 2 is a diagram of the formation of the Central core of the vortex and its measured parameters location relative to the water; Fig. 3 - the same, lateral view.The method is implemented on unit 1 is filled with water 2 containing a pump 3, a valve 4, the drain tube 5, a flow measuring device 6, water 7, mounted on the adapter pipe 8. At the bottom of the installation 1 under the intake 7 on the height H is a flat panel display 9 on the rod 10, the surface of which is filled with imitations of foreign objects 11, for example, cereals, gum, etc. is used For measuring the line 12.Education center core of the vortex (vortex) with the definition of its parameters relative to the intake is as follows.At the opening of the valve 4 and the inclusion of the work of the pump 3 the origin of the tube 5, the valve 4, which set the calculation mode to the expiration of the water 2, the drain tube 5, a flow measuring device 6, which tracks the estimated mode of the expiration of the water 2 through the intake 7. Before water 7 on the screen 9 is formed vortex (vortex), whose rotation moves imitators of foreign objects 11 to the center of the core of the vortex (vortex), forming their accumulation with the formation of the hills. The valve 4 and the pump 3 is disconnected and after the experiment to determine the location of the center core of the vortex 0 formed by hills, and its location with respect to water parameters X and Y, which are determined by the line 12.The proposed method allows for more accurate and better define the Central core of the vortex (vortex) and its location relative to the intake with the determination of quantitative parameters of its location after conducting experimental research. (56) 1. P. Zheng. Control of flow separation. M. , Mir, 1979, pp. 113-114.2. Epstein L. A. , Wolgram I. E. the Physics of the processes associated with the entrainment of spray and particles in the engine air intakes, M. , TSAGI, issue 2143, 1982, pp. 10-13. The method for DETERMINING the CENTER CORE of the VORTEX (VORTEX) AND ITS LOCATION is rnic, characterized in that before the suction of water through the intake on located under the intake screen is placed imitators of foreign objects, which, when the suction of water through the water accumulate, forming a hill, then determine the location of the center core of the vortex by measuring from the top of the hill to the front lower edge of the intake and from the top of the hill to the symmetry axis of intake.
FIELD: mechanical engineering; testing facilities.
SUBSTANCE: invention can be used for stand tests of pumps of any application. According to proposed method full pressure at pump input is maintained constant by means of reservoir with free surface of liquid exposed to constant (atmospheric) pressure installed in intake pipeline. Working liquid saturated vapor pressure at pump input is changed by heating. Periodical measurement of required parameters in process of liquid heating makes it possible to calculate sought for cavitation margin Δh. Method is implemented by test stand containing pump to be tested, output throttle, flow meter, heat exchanger, service tank, pipe fittings, all arranged in closed hydraulic circuit, and reservoir with free surface of working liquid in combination with capsule made of heat conducting material connected to circuit at pump input. Space of capsule is divided into two parts, one of which is partly filled with working liquid and sealed, and other communicates with circuit.
EFFECT: improved accuracy of measurements and simplified determination of pump cavitation characteristics.
3 cl, 1 dwg
SUBSTANCE: in through portion of pipe with choking of through portion cavitation flow lock mode is set, and in zone of low density value of critical pressure of cavitation and liquid flow are determined, which flow is used to determined liquid speed in pipe neck. Received critical pressure value of cavitation is aligned with pressure of saturated steam of pumped liquid, after that to specially built calculation graph dependencies of relative value of critical pressure of critical speed of flow in channel neck are applied in the moment of setting of lock mode with different concentration of cores target concentration of cores of cavitation of pumped liquid is determined.
EFFECT: higher efficiency.
FIELD: aviation industry.
SUBSTANCE: device helps to get real pattern of liquid pressure distribution which flows about "blown-about" object in water tunnel. Device has driven frequency pulse oscillator, frequency divider, control pulse counter, longitudinal contact multiplexer which connect capacitors with shelves, lateral contact multiplexer which connect the other output of capacitors, matching unit, analog-to-digital converter, indication unit, water tunnel, blown-about object, grid with capacitive detector.
EFFECT: improved precision of measurement.
FIELD: experimental hydrodynamics.
SUBSTANCE: method comprises making a model dynamically similar to the marine engineering structure in mass, sizes, location of the center of gravity, and inertia moment and mounting the model in the experimental tank by means of anchor-type links provided with dynamometers. The device comprises experimental tank and model provided with anchor-type links for connecting with the frame. The anchor-type links are provided with dynamometers and devices for control of initial tension. The frame has flat horizontal base, vertical pillars , and blocks. The base is provided with the members for securing the vertical pillars at specified points of the base. The vertical pillars are provided with blocks and members that are mounted for permitting movement along the pillars and their locking at a given position. The model is provided with the pickups of angular and linear movements. The outputs of the dynamometers and pickups of angular and linear displacements of the model are connected with the input of the computer.
EFFECT: expanded functional capabilities.
2 cl, 3 dwg
FIELD: measuring techniques.
SUBSTANCE: method and device can be used for measurement of hydraulic-dynamic resistance of different surfaces moving in fluid. Time of load descending, which load is kinetically connected with disc rotating in water, is compared when surface of load is coated with different matters.
EFFECT: simplicity at use; reduced cost.
2 cl, 1 dwg
SUBSTANCE: method comprises modeling the process of interaction of water flow with a rough surface by changing the working member of the sloping chute for a precision member with the smooth surface, measuring the height of the water flow in the entrance and exit sections of the chute by means of micrometer with measuring needle, determining the flow rate, and measuring the width of the chute. The smooth member is changed for the working member provided with a rough surface, and the height of the water in the exit section of the chute is measured.
EFFECT: simplified method.
FIELD: experimental hydromechanics; designing of equipment for conducting hydrodynamic and ice searches of marine engineering facility models in model testing basins.
SUBSTANCE: proposed device includes towing trolley with frame rigidly secured on it; this frame is provided with bar which is connected with model through dynamometers and bearing plate. Dynamometers form three-support force-measuring system; they are provided in each support in form of two interconnected elastic members; one elastic member is made in form of five-rod member provided with longitudinal and lateral force sensors; it is located between two flanges. Second elastic member of dynamometer is made in form of membrane-type elastic member whose membrane is located between rigid rim and rigid central part of this member provided with threaded rod with elastic hinge mounted over vertical axis perpendicularly relative to membrane. Membrane, rim and rigid central part with threaded rod and elastic hinge are made integral. Rim of membrane elastic members is rigidly connected with one of flanges of five-rod elastic member in such way that threaded rod is located along vertical axis of support and is rigidly connected via elastic hinge with bearing plate secured on model. Membrane is provided with resistance strain gages forming vertical force measuring bridge. Second flange of each five-rod member is connected with additional bearing plate secured on bar.
EFFECT: enhanced accuracy of measuring forces and moments.
FIELD: the invention refers to experimental hydrodynamics and may be used for definition of the resistance of small objects to a running flow at tests.
SUBSTANCE: the arrangement is fulfilled in the shape of a grate with the width Bt. and the height ht, deepened at the height T formed by rods with a step ▵ fixed in the supporting contour and is located at a certain distance in front of the tested object. At that it is installed with possibility of independent displacement relatively to the tested object and is fastened on the object and/or the body or probably on the bodies moving together with the tested object relatively to the test gondola. It is also may be formed by a system of private turbulators fulfilled in the shape of grates with a different size of cells, with possibility of their independent displacement relatively to each other including the fastening on different bodies and located primary in-series. The private turbulators may be fulfilled in the shape of grates particularly with different main direction of the rods of the grate. The mode is in locating the turbulator in front of the tested object with possibility of independent displacement relatively to the tested object and fastening on the object and/or on the body probably on the bodies moving together with the tested object particularly to test gondola. At that the position of the turbulator relatively to the tested object particularly the distance and displacement relatively to the tested object and also deepening and probably dimensions are chosen on the basis of comparison of results of the trial run of tarring of objects of different scales.
EFFECT: possibility of investigating of small models and revelation of the influence of resistance of the surface of the model.
6 cl, 3 dwg
SUBSTANCE: invention refers to experimental hydrodynamics, hydrodynamics and aerodynamics of airscrew and can be used in shipbuilding and aircraft building. Method includes force field created by airscrew rotation and carrier moving, use of visualising facilities and field structure registration by optical equipment. Thus airscrew rotary speed is established assuming production and stream maintenance of visualising facilities. Field is registered by scanning in two transversely-spaced planes, i.e. horizontal and vertical, in front of, and behind, the airscrew. Thus boundary layer, turbulence areas, increased and decreased pressure areas, airscrew expansion angles, and whole flow structure are showed.
EFFECT: high-accuracy picture of airscrew propeller environment flow.
5 cl, 16 dwg
SUBSTANCE: test stand for amphibious vehicles has basin with entrance and exit ramp, side walls, road, ramp and basin borders. From both sides of exit ramp pits are made in which ends of tubular shaft are embedded. Parallel arms-brackets of sheet metal are attached to the shaft equally spaced from axis. Between attached arms-brackets, spacer pipe is preliminary embedded on shaft which pipe has rectangular pawl with holes on both sides. By means of these holes the pipe is attached to captivating sheet located on symmetry axis of exit ramp. At the end of arms-brackets with lugs, cylinder is attached on axis. This cylinder is made along generator of curve corresponding to curve of vehicle front bumper. Tube rings with pawls are put on shaft ends. The pawls are fixed on pit floors. Spheroidal flanges are fixed on shaft ends to which flanges arms are attached, with brought-out from pits ends having lugs, and pneumatic cylinders are attached to arms from two sides.
EFFECT: reduction of scope of work during test stand construction and provides getting true data about capability of vehicle to move over water surface on tired wheels.