Flow field measurement device and flow field measurement method thereof

Abstract

The application discloses a flow field measuring device and a flow field measuring method thereof, wherein the flow field measuring device comprises an analog component, a gas supply system and a PIV measuring system, the analog component is used for simulating an outlet flow field of a vortex generator of a real combustion chamber, the analog component comprises an analog seat provided with a gas collecting cavity, the two ends of the analog seat in the axial direction are respectively provided with an air inlet hole and a mounting hole which are communicated with the gas collecting cavity, one end of the analog seat is provided with an optical glass cover which is communicated with the mounting hole, and the optical glass cover is used for simulating a limited space at the head of the combustion chamber; a secondary vortex generator is arranged in the mounting hole, the air inlet end of the secondary vortex generator is attached to a primary vortex generator, the air inlet end of the primary vortex generator is sequentially provided with a nozzle sleeve and a nozzle head; a spring is arranged outside the nozzle head, one end of the spring is abutted against the inner wall of the gas collecting cavity, the other end of the spring is abutted against the nozzle head, and the axis of the spring is coincident with the axis of the mounting hole. The concentricity of the primary vortex generator and the secondary vortex generator can be better ensured, and more real flow field characteristics can be obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of combustion chamber flow field test, in particular to a flow field measuring device and a flow field measuring method thereof. BACKGROUND

[0002] The combustion chamber vortex finder outlet flow field is very important for an aero-engine combustion chamber, and usually determines fuel atomization and mixing, head combustion organization, outlet temperature distribution and many other aspects to a great extent. Therefore, vortex finder outlet flow field test and measurement are often carried out during the development of the combustion chamber.

[0003] For the vortex finder outlet flow field, Pitot tube and hot wire and hot film instrument were used for flow field measurement in the early stage, but they belong to contact type single point measurement, which has great disturbance to the flow field and low measurement accuracy. Later, laser measurement methods such as Laser Doppler Velocimetry (LDV) and Phase Doppler Particle Analyzer (PDPA) were developed, which realized non-contact measurement, had no disturbance to the flow field and greatly improved the measurement accuracy, but they are still single point measurement, which still has great deficiencies and defects for the vortex finder outlet strong turbulent flow field. With the rapid development of computer technology, laser technology and image processing technology, Particle Image Velocimetry (PIV) emerged as the times require, which can realize non-contact, transient and full-field flow field measurement, and gradually becomes the main means of vortex finder outlet flow field measurement.

[0004] The existing vortex finder outlet flow field measuring device usually has a two-stage vortex finder on the vortex finder mounting disc in the gas cavity of the simulated combustion chamber, and a one-stage vortex finder is connected to the inlet of the two-stage vortex finder by gluing. During the simulation test measurement, compressed air mixed with tracer particles is injected into the gas cavity and enters the glass cover through the one-stage vortex finder and the two-stage vortex finder and is finally discharged into the atmosphere. The PIV measurement system is used to measure the vortex finder outlet flow field, and the measurement results are used to represent the real flow field structure of the vortex finder in the combustion chamber. However, the one-stage vortex finder and the two-stage vortex finder in the existing vortex finder outlet flow field measuring device are connected by gluing between the contact surfaces, which cannot guarantee the concentricity of the one-stage vortex finder and the two-stage vortex finder, resulting in certain differences between the simulated vortex finder state and the real engine, and the real flow field characteristics cannot be obtained. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to overcome the defect that the flow field measuring device in the prior art cannot guarantee the concentricity of the primary vortex generator and the secondary vortex generator, resulting in certain differences between the simulated vortex generator state and the real engine, and thus cannot obtain the real flow field characteristics, thereby providing a flow field measuring device and a flow field measuring method thereof.

[0006] According to the flow field measuring device provided by the first aspect of the present application, the outlet flow field of the vortex generator of the simulated engine combustion chamber is simulated and measured, and the flow field measuring device comprises:

[0007] The simulation assembly is used to simulate the outlet flow field of the vortex generator of the real combustion chamber, and comprises a simulation seat with a gas collection cavity, the two ends of the simulation seat along the axial direction are respectively provided with an air inlet hole and a mounting hole which are communicated with the gas collection cavity, one end of the simulation seat is provided with an optical glass cover which is communicated with the mounting hole, and the optical glass cover is used to simulate the limited space of the head of the combustion chamber; the secondary vortex generator is arranged in the mounting hole, the air inlet end of the secondary vortex generator is attached with the primary vortex generator, the air inlet end of the primary vortex generator is provided with a nozzle head, and the nozzle head is arranged between the one end of the primary vortex generator and the air inlet end of the primary vortex generator and is provided with a nozzle sleeve; the nozzle head is sleeved with a spring, one end of the spring abuts against the inner wall of the gas collection cavity, the other end of the spring abuts against the nozzle head, and the axis of the spring coincides with the axis of the mounting hole;

[0008] The gas supply system is communicated with the air inlet hole, and is used to inject the gas flow with tracer particles into the gas collection cavity;

[0009] The PIV measuring system is used to emit sheet laser to the optical glass cover and measure the outlet flow field of the vortex generator.

[0010] According to the flow field measuring device, the following technical effects are achieved: 1. During the assembly of the simulation assembly for the flow field measurement test, one end of the spring abuts against the inner wall of the gas collecting cavity, and the other end abuts against the nozzle head. At this time, the spring is in a compressed state, and the axis of the spring coincides with the axis of the mounting hole. The elastic force of the compressed spring is applied to the nozzle head and transmitted to the primary vortex flow device through the nozzle sleeve. The primary vortex flow device and the secondary vortex flow device are tightly sealed at the joint, and the axis of the spring coincides with the axis of the mounting hole after assembly, which guarantees the assembly concentricity between the primary vortex flow device and the secondary vortex flow device. The nozzle head and the nozzle sleeve are tightly sealed, and the assembly and disassembly are convenient. Compared with the prior art, the end surface of the primary vortex flow device and the nozzle sleeve is sealed by a simple sealing method. The device can fully consider the influence of the positive airflow at the outlet of the nozzle sleeve in the real engine combustion chamber on the outlet flow field of the vortex flow device, and the assembly state of the simulation assembly in the device is basically consistent with that in the real engine combustion chamber. The assembly convenience is improved. The actual state of the vortex flow device can be simulated, so that the outlet flow field characteristics of the vortex flow device in the real engine combustion chamber can be better obtained. 2. The gas inlet hole and the mounting hole are arranged on the two ends of the simulation seat along the axial direction and communicate with the gas collecting cavity. The optical glass cover is arranged on the end of the simulation seat away from the gas inlet hole and communicates with the mounting hole. During the flow field measurement test, the gas supply system injects the airflow of the compressed air with the tracer particles into the gas collecting cavity. The airflow enters the optical glass cover through the tightly sealed nozzle head, nozzle sleeve, primary vortex flow device, and secondary vortex flow device and is finally discharged into the atmosphere. The actual state of the vortex flow device is simulated. In this process, the PIV measurement system emits sheet laser to the measurement area of the optical glass cover, obtains the position image of the tracer particles in the measurement area, and analyzes and processes the position image to measure the flow field result. The measurement result can more truly represent the real flow field structure of the vortex flow device in the real combustion chamber.

[0011] Preferably, a limiting seat is arranged at the position corresponding to each mounting hole in the gas collecting cavity. A limiting hole is arranged at the end of the limiting seat facing the optical glass cover, and the axis of the limiting hole coincides with the axis of the mounting hole. The end of the spring away from the nozzle head is mounted in the limiting hole.

[0012] Preferably, the gas collecting cavity penetrates through the simulation seat along the axial direction. The mounting plate is detachably connected between the simulation seat and the optical glass cover. The mounting hole is arranged on the mounting plate. The support plate is detachably connected to the end of the simulation seat away from the mounting plate. The gas inlet hole is arranged on the support plate. The secondary vortex flow device is detachably connected in the mounting hole.

[0013] Preferably, a side of the support plate facing the mounting plate is provided with an inverted U-shaped plate, an assembly hole is formed through the inverted U-shaped plate along an axial direction at one end of the inverted U-shaped plate; the assembly hole is for the spring and the nozzle head to pass through and limit the spring; the limiting seat is arranged in the inverted U-shaped plate, the limiting hole coincides with the axis of the assembly hole; and / or the limiting hole communicates with the air inlet hole through the limiting seat, the limiting hole has a larger diameter than the air inlet hole; the axis of the nozzle head coincides with the axis of the air inlet hole.

[0014] Preferably, the simulation assembly is arranged vertically along an axial direction, the optical glass cover is arranged vertically along the axial direction at an end of the mounting plate away from the simulation seat; and / or the mounting plate is provided with a groove matching the optical glass cover at an end of the mounting plate facing the optical glass cover, the groove is formed around the optical glass cover along a contour of an end surface of the optical glass cover.

[0015] Preferably, the simulation seat is provided with a plurality of first threaded holes along a contour of an end of the simulation seat facing the mounting plate, the first threaded holes are parallel to the axial direction, the mounting plate is penetrated by a first through slot along the axial direction at a position corresponding to each of the first threaded holes, and a first fastening bolt is screwed through the first through slot and the first threaded hole when connected; and / or the simulation seat is provided with a plurality of second threaded holes along a contour of an end of the simulation seat facing the support plate, the second threaded holes are parallel to the axial direction, the support plate is penetrated by a second through slot along the axial direction at a position corresponding to each of the second threaded holes, and a second fastening bolt is screwed through the second through slot and the second threaded hole when connected.

[0016] Preferably, the gas supply system comprises a gas source, a pressure stabilizing tank, a filter and a dryer which are sequentially communicated by pipelines, an air outlet end of the dryer is communicated with the air inlet hole through a main air flow output pipeline; a tracer particle generator for providing tracer particles is further communicated with the main air flow output pipeline through an air flow output branch.

[0017] Preferably, the PIV measuring system comprises a computer, a synchronous controller, a laser, a light guide arm, a laser emitting end and a CCD camera, the light guide arm is connected with the laser emitting end and the laser respectively, and the light guide arm emits a sheet laser to the end of the optical glass cover away from the gas supply system to illuminate the tracer particles in the measuring area of the optical glass cover; the CCD camera is arranged perpendicularly to the measuring area of the optical glass cover to continuously acquire the position image of the tracer particles; the synchronous controller is electrically connected with the laser and the CCD camera respectively to control the laser emitting frequency of the laser and the time of acquiring the image of the CCD camera to match; the computer is electrically connected with the synchronous controller and the CCD camera respectively to send an instruction to the synchronous controller to control the laser and the CCD camera to work synchronously to measure, and the computer analyzes and processes the tracer particle image obtained by the measurement to obtain the outlet flow field.

[0018] According to the second aspect of the present application, a flow field measuring method is provided, which is applied to the flow field measuring device provided in the first aspect, and the flow field measuring method comprises the following steps:

[0019] The secondary vortex generators are installed in the mounting holes;

[0020] A primary vortex generator is attached to the air inlet end of each secondary vortex generator, and the nozzle sleeve and the nozzle head are sequentially arranged at the air inlet end of each primary vortex generator;

[0021] The spring is sleeved outside each nozzle head, one end of the spring is abutted against the inner wall of the gas collecting cavity, and the other end of the spring is abutted against the nozzle head, the assembled spring is compressed, and the axis of the assembled spring coincides with the axis of the mounting hole;

[0022] The optical glass cover is installed on the simulation seat;

[0023] The gas supply system is started to inject the gas flow with tracer particles into the gas collecting cavity, and the PIV measuring system is started to emit a sheet laser to the measuring area of the optical glass cover and acquire the position image of the tracer particles in the measuring area to analyze and process to obtain the vortex generator outlet flow field.

[0024] According to the flow field measuring method, at least the following technical effects are achieved:

[0025] 1. By setting a spring with its axis coinciding with the axis of the mounting hole outside the nozzle head, and the spring is in a compressed state after assembly (that is, there is a pre-tightening force); during the flow field measurement test after assembly, the elastic force of the compressed spring is applied to the nozzle head and transmitted to the primary vortex through the nozzle sleeve, which can make the primary vortex and the secondary vortex tightly fit and seal, and the axis of the assembled spring coincides with the axis of the mounting hole, which can well ensure the assembly concentricity between the primary vortex and the secondary vortex; it can also make the nozzle head and the nozzle sleeve, and the nozzle sleeve and the primary vortex tightly fit and seal, and it is easy to disassemble and assemble, compared with the existing technology which uses simple plugging method to plug the end face of the primary vortex and the nozzle sleeve, this measurement method can fully consider that there is a positive airflow at the outlet of the nozzle sleeve in the real engine combustion chamber which has a greater impact on the vortex outlet flow field, so that the assembly state of the simulation assembly in the measurement process is basically consistent with the real engine combustion chamber, and the assembly convenience is also improved; it can better simulate the actual state of the vortex, so as to better obtain the outlet flow field characteristics of the vortex in the real engine combustion chamber.2. Also by setting an air inlet hole and a mounting hole communicating with the gas collection chamber at the two ends of the simulation seat along the axial direction respectively, and setting an optical glass cover communicating with the mounting hole at the end of the simulation seat away from the air inlet hole along the axial direction; during the flow field measurement test, the gas flow of compressed air with tracer particles is injected into the gas collection chamber through the gas supply system, and the gas flow enters the optical glass cover through the tightly fitted and sealed nozzle head, nozzle sleeve, primary vortex and secondary vortex and finally is discharged into the atmosphere, which better simulates the actual state of the vortex; in this process, the PIV measurement system emits sheet laser to the measurement area of the optical glass cover and obtains the position image of the tracer particles in the measurement area for analysis and processing and measures the flow field results, which can more truly represent the real flow field structure of the vortex in the real combustion chamber.

[0026] Preferably, the simulation assembly is vertically arranged along the height direction, the optical glass cover is arranged at the relatively upper end of the simulation seat along the height direction; the gas collection chamber penetrates through the simulation seat along the axial direction; the installation plate is detachably connected between the simulation seat and the optical glass cover, the mounting hole is arranged on the installation plate; the support plate is detachably connected to the relatively lower end of the end of the simulation seat away from the installation plate along the height direction, the air inlet hole is arranged on the support plate; the secondary vortex is detachably connected in the mounting hole;

[0027] Before the flow field measurement, according to the different models of the vortex flow device for the flow field test, the sealing and cooperation of vortex flow devices of different models and different structures can be realized by replacing the corresponding nozzle head, nozzle sleeve and mounting plate with corresponding size mounting holes; or according to the different number of vortex flow devices for the flow field test, the flow field measurement can be realized by replacing the mounting plate with corresponding number of mounting holes, the support plate with corresponding number of air inlet holes and increasing or decreasing corresponding number of the spring, the nozzle head and the nozzle sleeve.

[0028] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0030] Figure 1 A structural schematic diagram of a flow field measurement device according to an embodiment of the present application;

[0031] Figure 2 A structural schematic diagram of a simulation assembly according to an embodiment of the present application;

[0032] Figure 3 A structural schematic diagram of a nozzle sleeve according to an embodiment of the present application;

[0033] Figure 4 An enlarged schematic diagram of part of the structure of a simulation assembly according to an embodiment of the present application.

[0034] Explanation of reference signs:

[0035] 1-simulation assembly, 11-simulation seat, 111-gas collection cavity, 112-air inlet hole, 113-limiting seat, 114-limiting hole, 12-optical glass cover, 121-measurement area, 13-secondary vortex flow device, 14-primary vortex flow device, 15-nozzle head, 151- boss, 16-nozzle sleeve, 161-outlet, 162-carbon deposition hole, 17-spring, 18-mounting plate, 19-supporting plate, 191-inverted U-shaped plate, 192-assembly hole;

[0036] 2-gas supply system, 21-main gas flow output pipeline, 22-gas flow output branch, 23-tracer particle generator;

[0037] 31 - computer, 32 - synchronization controller, 33 - laser, 34 - light guide arm, 35 - laser emission end, 36 - CCD camera. DETAILED DESCRIPTION

[0038] The technical solutions of the present application will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0039] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0040] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0042] With the rapid development of computer technology, laser technology and image processing technology, the particle image velocimetry (PIV) technology emerges as the times require, which can realize non-contact, transient and full-field flow field measurement, and gradually becomes the main means for measuring the flow field at the outlet of a vortex device. The measurement principle of PIV technology is to scatter tracer particles (usually with a particle size of about 1 μm) in the flow field to be measured, to illuminate the flow field to be measured twice in a very short time (usually in the order of μs) by using double-pulse sheet laser, to record the particle position pictures twice by using double-frame double-exposure camera, to obtain the velocity field of the tracer particles in the whole plane by cross-correlation calculation and processing, and then to use the velocity of the tracer particles to represent the velocity of the air flow field at the corresponding position.

[0043] The existing flow field measurement device usually ignores the influence of the nozzle and the nozzle sleeve on the vortex finder outlet flow field in the process of measuring the vortex finder outlet flow field, usually adopts a simple plugging method to plug the end surface of the primary vortex finder matched with the nozzle, and the contact surface between the primary vortex finder and the secondary vortex finder is connected through gluing, which cannot guarantee the concentricity of the primary vortex finder and the secondary vortex finder, resulting in certain differences from the vortex finder in the real engine combustion chamber and failing to obtain the real flow field characteristics.

[0044] Embodiment one

[0045] As Figures 1 to 4 The flow field measurement device provided by the embodiment is shown in the figure, which is applied to simulate and measure the outlet flow field of the vortex finder of the real aero-engine combustion chamber, and the flow field measurement device comprises a simulation assembly 1, a gas supply system 2 and a PIV measurement system; the simulation assembly 1 is used for simulating the outlet flow field of the vortex finder of the real combustion chamber, and the simulation assembly 1 comprises a simulation seat 11 provided with a gas collecting cavity 111, the simulation seat 11 is provided with an air inlet hole 112 and a mounting hole communicating with the gas collecting cavity 111 at the two ends along the axial direction, one end of the simulation seat 11 is provided with an optical glass cover 12 communicating with the mounting hole, and the optical glass cover 12 is used for simulating the limited space of the combustion chamber head; a secondary vortex finder 13 is arranged in the mounting hole, a primary vortex finder 14 is attached to the air inlet end of the secondary vortex finder 13, a nozzle head 15 is arranged at the air inlet end of the primary vortex finder 14, and a nozzle sleeve 16 is arranged between one end of the nozzle head 15 facing the primary vortex finder 14 and the air inlet end of the primary vortex finder 14; a spring 17 is arranged outside the nozzle head 15, one end of the spring 17 abuts against the inner wall of one end of the gas collecting cavity 111 away from the optical glass cover 12 along the axial direction, the other end of the spring 17 abuts against the nozzle head 15, and the axis of the spring 17 coincides with the axis of the mounting hole; the gas supply system 2 communicates with the air inlet hole 112, and the gas supply system 2 is used for injecting the airflow with tracer particles into the gas collecting cavity 111; the PIV measurement system is used for emitting sheet laser to the optical glass cover 12 and measuring the outlet flow field of the secondary vortex finder 13. It can be understood that the axial direction in the embodiment of the application refers to the axial direction shown in the figure; the vortex finder comprises the primary vortex finder 14 and the secondary vortex finder 13. Figure 2

[0046] ​Compared with the prior art, in the process of assembling the simulation assembly 1 for flow field measurement test, one end of the spring 17 abuts against the inner wall of the end of the gas collecting cavity 111 away from the optical glass cover 12 in the axial direction, and the other end abuts against the nozzle head 15, at this time, the spring 17 is in a compressed state, and the axis of the spring 17 coincides with the axis of the mounting hole, the elastic force of the compressed spring 17 is applied to the nozzle head 15 and is transmitted to the primary vortex generator 14 through the nozzle sleeve 16, which can make the primary vortex generator 14 and the secondary vortex generator 13 tightly and effectively seal, and the axis of the spring 17 coincides with the axis of the mounting hole after assembly, which well guarantees the assembly concentricity between the primary vortex generator 14 and the secondary vortex generator 13; and can make the nozzle head 15 and the nozzle sleeve 16 and the nozzle sleeve 16 and the primary vortex generator 14 tightly seal, and is convenient to disassemble and assemble, compared with the prior art, the end face of the primary vortex generator 14 and the nozzle sleeve 16 is sealed by a simple plugging method, the device can fully consider that there is a positive airflow at the outlet 161 of the nozzle sleeve 16 in the real engine combustion chamber, which has a greater influence on the vortex generator outlet flow field, so that the assembly state of the simulation assembly 1 in the device is basically consistent with that in the real engine combustion chamber, and the assembly convenience is improved; the actual state of the vortex generator can be better simulated, so that the outlet flow field characteristics of the vortex generator in the real engine combustion chamber can be better obtained. In the embodiment of the application, the gas inlet hole 112 and the mounting hole are arranged on the two ends of the simulation seat 11 in the axial direction and communicate with the gas collecting cavity 111, and the optical glass cover 12 is arranged on the end of the simulation seat 11 away from the gas inlet hole 112 and communicates with the mounting hole; in the process of flow field measurement test, the gas flow of compressed air with tracer particles is injected into the gas collecting cavity 111 through the gas supply system 2, the gas flow enters the optical glass cover 12 through the tightly sealed nozzle head 15, nozzle sleeve 16, primary vortex generator 14 and secondary vortex generator 13 in sequence and is finally discharged into the atmosphere, which better simulates the actual state of the vortex generator; in this process, the PIV measurement system emits sheet laser to the measurement area 121 of the optical glass cover 12 and obtains the position image of the tracer particles in the measurement area 121 for analysis and processing and measures the flow field result, which can more truly represent the real flow field structure of the vortex generator in the real combustion chamber. It can be understood that the flow direction of the positive airflow in the embodiment is parallel to the direction of air flowing from the primary vortex generator 14 to the secondary vortex generator 13; the spring 17 in the embodiment can be a gas spring, a spiral spring and a rubber spring.

[0047] It should be noted that the axial center distance between the two adjacent vortices installed on the mounting hole of the simulation seat 11 (i.e. the secondary vortex 13 assembled with the primary vortex 14) is consistent with the axial center distance between the two adjacent vortices of the actual engine combustion chamber. The nozzle head 15 in the embodiment is used to simulate the actual nozzle structure in the combustion chamber, and the size of the nozzle head 15 is consistent with the size of the actual nozzle structure; the nozzle sleeve 16 in the embodiment is used to simulate the actual nozzle sleeve structure in the combustion chamber, and the size of the nozzle sleeve 16 in the embodiment is consistent with the size of the actual nozzle sleeve structure; the gas collection cavity 111 in the embodiment is designed according to the size of the inner cavity of the combustion chamber; the size of the optical glass cover 12 in the embodiment is determined according to the actual flame tube height of the engine combustion chamber and the distance between the head vortexes; so as to obtain more real vortex outlet flow field characteristics.

[0048] As shown in Figure 2 and Figure 4 , specifically, the nozzle head 15 is provided with a boss 151 on the side wall of the end away from the air inlet hole 112 in the axial direction, and one end of the spring 17 abuts against the boss 151.

[0049] As shown in Figure 2 , in some embodiments of the present application, a limiting seat 113 is arranged at a position corresponding to each mounting hole in the gas collection cavity 111, and a limiting hole 114 is arranged at one end of the limiting seat 113 towards the optical glass cover 12, the limiting hole 114 coincides with the axis of the mounting hole; one end of the spring 17 away from the nozzle head 15 is installed in the limiting hole 114. By limiting and fixing one end of the spring 17 through the limiting hole 114, the axis of the assembled spring 17 can be effectively ensured to coincide with the axis of the mounting hole, so that the assembly concentricity between the primary vortex 14 and the secondary vortex 13 can be better guaranteed, and more real vortex outlet flow field characteristics can be obtained.

[0050] As shown in Figure 2As shown, in some embodiments of the present application, the gas collecting cavity 111 extends through the simulation seat 11 in the axial direction; the simulation seat 11 is detachably connected with the mounting plate 18, the mounting hole is arranged on the mounting plate 18; the simulation seat 11 is detachably connected with the support plate 19 at the end away from the mounting plate 18 in the axial direction, the air inlet hole 112 is arranged on the support plate 19; the secondary vortex generator 13 is detachably connected in the mounting hole. By setting the simulation assembly 1 as a detachable structure, during the flow field measurement test, different types and structures of vortex generators can be sealed and matched by replacing the nozzle head 15 and the nozzle sleeve 16 corresponding to the type of the vortex generator used in the actual test and replacing the mounting plate 18 with mounting holes for mounting the vortex generator of the corresponding type; different numbers of vortex generators can be tested by replacing the mounting plate 18 with the same number of mounting holes, replacing the support plate 19 with the same number of air inlet holes 112, and adding or reducing the corresponding number of springs 17, nozzle heads 15 and nozzle sleeves 16. The device has strong versatility, low test cost and high efficiency. It can be understood that the size of the inner cavity of the real combustion chamber does not change (i.e. the size of the gas collecting cavity 111 does not change) during the outlet flow field measurement test of different types of vortex generators or during the outlet flow field measurement test of the same type of head vortex generator with different numbers, so the simulation seat 11 does not need to be replaced; the size of the air inlet end of the nozzle head 15 of different types remains the same, and the only difference is that the size of the end of the nozzle head 15 of different types matched with the air inlet end of the primary vortex generator 14 is different, so the type of the spring 17 does not need to be replaced during the outlet flow field measurement test of different types of vortex generators.

[0051] The detachable connection structure between the simulation seat 11 and the mounting plate 18 is not limited in this embodiment. In order to improve the tightness of the connection between the two on the basis of facilitating disassembly, preferably, four first threaded holes are arranged on the end face of the simulation seat 11 facing the mounting plate 18 along the contour of the end face of the simulation seat 11, the first threaded holes are parallel to the axial direction, and a first through slot is arranged on the mounting plate 18 corresponding to the position of each first threaded hole in the axial direction. In use, the first fastening bolt is screwed through the first through slot and the first threaded hole. Of course, in other embodiments, the detachable connection structure between the simulation seat 11 and the mounting plate 18 can also be a transition fit type of clamping portion and clamping slot plug-in cooperation or other structures.

[0052] This embodiment does not limit the detachable connection structure between the simulation base 11 and the support plate 19. To improve the tightness of the connection while facilitating disassembly, preferably, the simulation base 11 has four second threaded holes along the contour of its end face facing the support plate 19. These second threaded holes are parallel to the axial direction. A second through slot is provided on the support plate 19 corresponding to each of the second threaded holes, extending axially. In use, a second fastening bolt passes through the second through slot and screws into the second threaded hole. Of course, in other embodiments, the detachable connection structure between the simulation base 11 and the support plate 19 can also be configured as a transitional fit, a snap-fit, or a slot insertion fit, or other structures.

[0053] This embodiment does not limit the detachable connection structure between the mounting hole and the secondary vortex generator 13. To ensure stable assembly of the secondary vortex generator 13 within the mounting hole for flow field measurement experiments while maintaining detachability, preferably, the mounting hole has an internal thread, and the outer wall of the secondary vortex generator 13 has a threaded portion that matches the internal thread. Of course, in other embodiments, the detachable connection structure between the simulation base 11 and the support plate 19 can also be configured as a transitional fit plug-in fit or other structures.

[0054] like Figure 2 As shown in Figure 4, in some embodiments of the present invention, the support plate 19 is provided with an inverted U-shaped plate 191 on the side facing the mounting plate 18, and an assembly hole 192 is formed axially through one end of the inverted U-shaped plate 191 facing the mounting plate 18; the assembly hole 192 allows the spring 17 and the nozzle head 15 to pass through and limits the spring 17; the limiting seat 113 is disposed in the inverted U-shaped plate 191, and the limiting hole 114 coincides with the axis of the assembly hole 192. The spring 17 is axially limited at both ends by the assembly hole 192 and the limiting hole 114, and the axis of the assembly hole 192 and the axis of the limiting hole 114 are both coincident with the axis of the mounting hole. This can better ensure that the axis of the assembled spring 17 is coincident with the axis of the mounting hole, thereby better ensuring the concentricity of the assembly between the first-stage vortex generator 14 and the second-stage vortex generator 13, and ensuring a tight fit and seal between the first-stage vortex generator 14 and the second-stage vortex generator 13, thus obtaining more realistic vortex generator outlet flow field characteristics.

[0055] like Figure 2As shown, in some embodiments of the present invention, the limiting hole 114 penetrates the limiting seat 113 and communicates with the air inlet 112, and the diameter of the limiting hole 114 is larger than the diameter of the air inlet 112; the axis of the nozzle head 15 coincides with the axis of the air inlet 112. By aligning the axis of the air inlet 112 with the axis of the nozzle head 15, the airflow entering the air collecting chamber 111 first impacts the nozzle head 15 and then disperses to the surroundings, which stabilizes the airflow and further makes the tracer particles more evenly distributed; at the same time, by using nozzle head 15 and nozzle sleeve 16 with the same dimensions as the actual nozzle structure and the actual nozzle sleeve structure, the influence of nozzle head 15 and nozzle sleeve 16 on the vortex outlet flow field in the engine is well simulated.

[0056] like Figure 2 As shown, in some embodiments of the present invention, the simulation component 1 is arranged vertically along the axial direction, and the optical glass cover 12 is arranged vertically along the axial direction at one end of the mounting plate 18 away from the simulation base 11; the spring 17 in the simulation component 1 arranged vertically along the axial direction is in a vertical state, so that the weight of the spring 17 itself is applied to the spring 17 in a vertical direction. Compared with the horizontally arranged spring 17, it can better ensure that the axis of the assembled spring 17 coincides with the axis of the mounting hole, thereby better ensuring the concentricity of the assembly between the first-stage eddy current generator 14 and the second-stage eddy current generator 13.

[0057] This embodiment does not limit the detachable connection structure between the mounting plate 18 and the optical glass cover 12. To more stably and detachably mount the axially vertically arranged optical glass cover 12 onto the mounting plate 18, preferably, the mounting plate 18 has a groove matching the optical glass cover 12 at one end facing the optical glass cover 12. This groove is formed around the axis of the optical glass cover 12 along the end face contour of the optical glass cover 12. The end of the optical glass cover 12 facing the mounting plate 18 is seamlessly inserted into the groove. During assembly, the optical glass cover 12 can achieve a good sealing fit with the mounting plate 18 solely through its own weight, greatly improving the operability and efficiency of the experiment. To further improve the sealing performance between the optical glass cover 12 and the mounting plate 18 and facilitate better measurement results, specifically, the optical glass cover 12 is made of heavy-duty optical glass with high light transmittance. Of course, in other embodiments, the detachable connection structure between the mounting plate 18 and the optical glass cover 12 can also be set as a bolt and nut connection or other structures.

[0058] It should be noted that if the cross-sectional area of the optical glass cover 12 is rectangular, the arrangement shape of the groove is a rectangular profile with the axis of the optical glass cover 12 as the geometric center; if the cross-sectional area of the optical glass cover 12 is circular, the arrangement shape of the groove is a circular ring profile with the axis of the optical glass cover 12 as the axis.

[0059] In some embodiments of the present application, the gas supply system 2 comprises a gas source, a pressure stabilizing tank, a filter and a dryer which are sequentially communicated by pipes, and the outlet of the dryer is communicated with the inlet hole 112 through a main gas flow output pipeline 21; a tracer particle generator 23 for providing tracer particles is also communicated with the main gas flow output pipeline 21 through a gas flow output branch 22. The compressed air provided by the gas source forms a main gas flow for testing after being processed by the pressure stabilizing tank, the filter and the dryer in sequence, and is delivered to the gas collection cavity 111 through the main gas flow output pipeline 21, while part of the gas flow enters the tracer particle generator 23 through the gas flow output branch 22 to generate tracer particles with small atomized particle size, and then the gas flow carrying the tracer particles comes out of the tracer particle generator 23 and enters the gas collection cavity 111 together with the main gas flow. During the whole gas supply process, the gas supply system 2 can greatly mix the tracer particles.

[0060] As shown in Figure 1 In some embodiments of the present application, the PIV measurement system comprises a computer 31, a synchronous controller 32, a laser 33, a light guide arm 34, a laser emitting end 35 and a CCD camera 36, the light guide arm 34 is connected with the laser emitting end 35 and the laser 33 respectively, and emits sheet laser to the end of the optical glass cover 12 away from the gas supply system 2 to illuminate the tracer particles in the measurement area 121 of the optical glass cover 12; the CCD camera 36 is arranged perpendicular to the measurement area 121 of the optical glass cover 12 to continuously acquire the position images of the tracer particles; the synchronous controller 32 is electrically connected with the laser 33 and the CCD camera 36 respectively to control the laser emission frequency of the laser 33 and the time of acquiring images by the CCD camera 36 to match; the computer 31 is electrically connected with the synchronous controller 32 and the CCD camera 36 respectively, the computer 31 sends instructions to the synchronous controller 32 to control the laser 33 and the CCD camera 36 to work synchronously for measurement, and the tracer particle images measured by the CCD camera 36 are analyzed and processed by the computer 31 to obtain the outlet flow field; at the same time, because the synchronous controller 32 is electrically connected with the laser 33, the CCD camera 36 and the computer 31 respectively, the laser emission of the laser 33, the image shooting of the CCD camera 36 and the image analysis and processing of the computer 31 can be effectively controlled synchronously.

[0061] The working process of the PIV measurement system is as follows: the computer 31 controls the laser 33 to emit laser by sending a command to the synchronous controller 32, the laser is converted into sheet laser after passing through the light guide arm 34, and is transmitted to the measurement area 121 of the optical glass cover 12 through the laser emission end 35. At the same time, the synchronous controller 32 controls the CCD camera 36 to record two tracer particle images through the camera endoscope, then the computer 31 obtains the velocity field of the entire tracer particle by performing cross-correlation calculation and processing on the tracer particle images, finally the velocity of the air flow field at the corresponding position is represented by the velocity of the tracer particle, so as to obtain the flow characteristics of the flow field at the outlet of the vortex device of the combustion chamber. The specific cross-correlation calculation process belongs to the conventional PIV technology, and thus is not described herein.

[0062] Embodiment Two

[0063] As Figures 1 to 4 shown is a flow field measurement method for simulating and measuring the flow field at the outlet of the vortex device of a real aero-engine combustion chamber by using the flow field measurement device described in Embodiment One, the flow field measurement comprising the following steps:

[0064] The secondary vortex device 13 is installed in the mounting hole;

[0065] A primary vortex device 14 is attached to the air inlet end of each secondary vortex device 13, and the nozzle sleeve 16 and the nozzle head 15 are sequentially arranged at the air inlet end of each primary vortex device 14;

[0066] The spring 17 is sleeved outside each nozzle head 15, one end of the spring 17 abuts against the inner wall of the end of the gas collection cavity 111 axially away from the optical glass cover 12, and the other end abuts against the nozzle head 15, the assembled spring 17 is compressed, and the axis of the assembled spring 17 coincides with the axis of the mounting hole;

[0067] The optical glass cover 12 is installed on the simulation seat 11;

[0068] The gas supply system 2 is started to inject the gas flow with tracer particles into the gas collection cavity 111, and the PIV measurement system is started to emit sheet laser to the measurement area 121 of the optical glass cover 12 and obtain the position image of the tracer particles in the measurement area 121 for analysis and processing to obtain the flow field at the outlet of the vortex device.

[0069] Compared with the prior art, the embodiment of the present application is characterized in that the spring 17 coaxial with the mounting hole is arranged outside the nozzle head 15, and the spring 17 is in a compressed state (i.e. there is a pre-tightening force) after assembly; during the flow field measurement test after assembly, the elastic force of the compressed spring 17 is applied to the nozzle head 15 and is transmitted to the primary vortex generator 14 through the nozzle sleeve 16, which can make the primary vortex generator 14 and the secondary vortex generator 13 tightly and effectively seal at the joint, and the coaxiality of the spring 17 after assembly and the mounting hole is good, which guarantees the assembly concentricity between the primary vortex generator 14 and the secondary vortex generator 13; and the nozzle head 15 and the nozzle sleeve 16 and the nozzle sleeve 16 and the primary vortex generator 14 can be tightly sealed, and the assembly and disassembly are convenient; compared with the prior art, the end face of the primary vortex generator 14 and the nozzle sleeve 16 is sealed by a simple sealing method, the present measurement method can fully consider that the outlet 161 of the nozzle sleeve 16 in the real engine combustion chamber will also have a positive airflow that has a greater impact on the vortex generator outlet flow field, so that the assembly state of the simulation assembly 1 in the measurement process is basically consistent with that in the real engine combustion chamber, and the assembly convenience is improved; the actual state of the vortex generator can be better simulated, so that the outlet flow field characteristics of the vortex generator in the real engine combustion chamber can be better obtained. The embodiment of the present application is also characterized in that the air inlet hole 112 and the mounting hole communicating with the gas collection cavity 111 are arranged at the two ends of the simulation seat 11 along the axial direction, and the optical glass cover 12 communicating with the mounting hole is arranged at the end of the simulation seat 11 away from the air inlet hole 112 along the axial direction; during the flow field measurement test, the compressed air flow with tracer particles is injected into the gas collection cavity 111 through the gas supply system 2, and the air flow enters the optical glass cover 12 through the tightly sealed nozzle head 15, nozzle sleeve 16, primary vortex generator 14 and secondary vortex generator 13 and is finally discharged into the atmosphere, which better simulates the actual state of the vortex generator; in this process, the PIV measurement system emits sheet laser to the measurement area 121 of the optical glass cover 12 and obtains the position image of the tracer particles in the measurement area 121 for analysis and processing and measures the flow field result, which can more truly represent the real flow field structure of the vortex generator in the real combustion chamber.

[0070] As shown in the drawings, Figure 2 in some embodiments of the present application, the gas collection cavity 111 penetrates the simulation seat 11 along the axial direction; the mounting plate 18 is detachably connected between the simulation seat 11 and the optical glass cover 12, the mounting hole is arranged on the mounting plate 18, and the secondary vortex generator 13 is detachably connected in the mounting hole; the support plate 19 is detachably connected to the end of the simulation seat 11 away from the mounting plate 18 along the axial direction, and the air inlet hole 112 is arranged on the support plate 19;

[0071] Before the flow field measurement, the sealing and matching of different types and structures of vortex finder can be realized by replacing the nozzle head 15 and nozzle sleeve 16 corresponding to the type of the vortex finder to be tested and replacing the mounting plate 18 with mounting holes for mounting the vortex finder of the corresponding type according to the type of the vortex finder to be tested. The flow field measurement test can also be realized by replacing the mounting plate 18 with mounting holes corresponding to the number of vortex finders, replacing the support plate 19 with a corresponding number of air inlet holes 112, and increasing or decreasing a corresponding number of springs 17, nozzle heads 15 and nozzle sleeves 16 according to the number of vortex finders to be tested. The measurement method has strong universality, low test cost and high efficiency. It can be understood that the size of the inner cavity of the real combustion chamber does not change (i.e. the size of the gas collection cavity 111 does not change) when the outlet flow field measurement test of different types of vortex finders is carried out or when the outlet flow field measurement test of the same type of different numbers of head vortex finders is carried out, so the simulation seat 11 does not need to be replaced.

[0072] Obviously, the above embodiments are only examples for the purpose of clarity, and are not limitations on the embodiments. Based on the above description, other different forms of changes or variations can be made by those of ordinary skill in the art. All embodiments do not need to be exhausted and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A flow field measurement device for simulating and measuring the outlet flow field of a swirler of an engine combustion chamber, characterized in that, The flow field measuring device comprises: An analog component (1) for simulating the outlet flow field of a vortex device of a real combustion chamber, the analog component (1) comprising an analog seat (11) with a gas collection cavity (111) arranged therein, the analog seat (11) being provided with an air inlet hole (112) and a mounting hole communicating with the gas collection cavity (111) at two axial ends thereof, the analog seat (11) being provided with an optical glass cover (12) communicating with the mounting hole at one end thereof, the optical glass cover (12) being used for simulating a limited space at a head of the combustion chamber; a secondary vortex device (13) being arranged in the mounting hole, a primary vortex device (14) being arranged at the air inlet end of the secondary vortex device (13), a nozzle head (15) being arranged at the air inlet end of the primary vortex device (14), a nozzle sleeve (16) being arranged between the nozzle head (15) and the air inlet end of the primary vortex device (14) at one end of the nozzle head (15) facing the primary vortex device (14); a spring (17) being arranged outside the nozzle head (15), one end of the spring (17) abutting against an inner wall of the gas collection cavity (111), the other end of the spring (17) abutting against the nozzle head (15), an axis of the spring (17) coinciding with an axis of the mounting hole; A gas supply system (2) communicating with the air inlet hole (112), the gas supply system (2) being used for injecting a gas flow with tracer particles into the gas collection cavity (111); A PIV measuring system for emitting sheet laser to the optical glass cover (12) and measuring the outlet flow field of the vortex device.

2. The flow field measurement device of claim 1, wherein, A limiting seat (113) is arranged in the gas collection cavity (111) at a position corresponding to each mounting hole, the limiting seat (113) being provided with a limiting hole (114) at one end thereof facing the optical glass cover (12), the limiting hole (114) coinciding with the axis of the mounting hole; one end of the spring (17) away from the nozzle head (15) being arranged in the limiting hole (114).

3. A flow field measurement device according to claim 2, wherein, The gas collection cavity (111) penetrates the analog seat (11) along an axial direction; the analog seat (11) and the optical glass cover (12) are detachably connected with a mounting plate (18), the mounting hole being arranged on the mounting plate (18), the secondary vortex device (13) being detachably connected in the mounting hole; the analog seat (11) is detachably connected with a support plate (19) at one end thereof away from the mounting plate (18), the air inlet hole (112) being arranged on the support plate (19).

4. The flow field measurement device of claim 3, wherein, The side of the support plate (19) facing the mounting plate (18) is provided with an inverted U-shaped plate (191), one end of the inverted U-shaped plate (191) facing the mounting plate (18) is formed with a mounting hole (192) penetrating in the axial direction; the mounting hole (192) is for the spring (17) and the nozzle head (15) to pass through and limit the spring (17); the limiting seat (113) is arranged in the inverted U-shaped plate (191), the limiting hole (114) coincides with the axis of the mounting hole (192); and / or, the limiting hole (114) communicates with the air inlet hole (112) through the limiting seat (113) penetrating the limiting seat (113), the hole diameter of the limiting hole (114) is larger than the hole diameter of the air inlet hole (112); the axis of the nozzle head (15) coincides with the axis of the air inlet hole (112).

5. The flow field measurement device of claim 3, wherein, The simulation assembly (1) is arranged vertically in the axial direction, the optical glass cover (12) is arranged vertically in the axial direction at one end of the mounting plate (18) away from the simulation seat (11); and / or, one end of the mounting plate (18) facing the optical glass cover (12) is provided with a groove matched with the optical glass cover (12), the groove is formed around the axis of the optical glass cover (12) along the end surface profile of the optical glass cover (12).

6. The flow field measurement device of claim 3, wherein, The simulation seat (11) is provided with a plurality of first threaded holes along its profile at one end facing the mounting plate (18), the first threaded holes are parallel to the axial direction, the mounting plate (18) is penetrated in the axial direction at a position corresponding to each first threaded hole, and a first through slot is arranged, when connected, a first fastening bolt is screwed through the first through slot and the first threaded hole; and / or, the simulation seat (11) is provided with a plurality of second threaded holes along its profile at one end facing the support plate (19), the second threaded holes are parallel to the axial direction, the support plate (19) is penetrated in the axial direction at a position corresponding to each second threaded hole, and a second through slot is arranged, when connected, a second fastening bolt is screwed through the second through slot and the second threaded hole.

7. The flow field measurement device of claim 1, wherein, The gas supply system (2) comprises a gas source, a pressure stabilizing tank, a filter and a dryer which are sequentially communicated by pipelines, the air outlet end of the dryer is communicated with the air inlet hole (112) through a main air flow output pipeline (21); the main air flow output pipeline (21) is also communicated with a tracer particle generator (23) for providing tracer particles through an air flow output branch (22).

8. The flow field measurement device of claim 1, wherein, The PIV measurement system comprises a computer (31), a synchronous controller (32), a laser (33), a light guide arm (34), a laser emitting end (35) and a CCD camera (36), the light guide arm (34) is connected with the laser emitting end (35) and the laser (33) respectively, and emits a sheet laser to the end of the optical glass cover (12) away from the gas supply system (2) to illuminate the tracer particles in the measurement area (121) of the optical glass cover (12); the CCD camera (36) is arranged perpendicular to the measurement area (121) of the optical glass cover (12) to continuously acquire the position image of the tracer particles; the synchronous controller (32) is electrically connected with the laser (33) and the CCD camera (36) respectively to control the laser emitting frequency of the laser (33) and the time of acquiring the image of the CCD camera (36) to match; the computer (31) is electrically connected with the synchronous controller (32) and the CCD camera (36) respectively to send an instruction to the synchronous controller (32) to control the laser (33) and the CCD camera (36) to work synchronously to measure, and the tracer particle image obtained by the measurement is analyzed and processed by the computer (31) to obtain the outlet flow field.

9. A flow field measurement method, characterized in that it is applied to the flow field measurement device of any one of claims 1 to 8, and comprises the following steps: installing the secondary vortex generators (13) in the mounting holes; attaching a primary vortex generator (14) to the gas inlet end of each secondary vortex generator (13), and sequentially arranging the nozzle sleeve (16) and the nozzle head (15) on the gas inlet end of each primary vortex generator (14); sleeving the spring (17) outside each nozzle head (15), abutting one end of the spring (17) to the inner wall of the gas collection cavity (111), and abutting the other end of the spring (17) to the nozzle head (15), the assembled spring (17) is compressed, and the axis of the assembled spring (17) coincides with the axis of the mounting hole; installing the optical glass cover (12) on the simulation seat (11); starting the gas supply system (2) to inject a gas flow with tracer particles into the gas collection cavity (111), while starting the PIV measurement system to emit a sheet laser to the measurement area (121) of the optical glass cover (12) and acquire the position image of the tracer particles in the measurement area (121) for analysis and processing to obtain the vortex generator outlet flow field.

10. The flow field measurement method of claim 9, wherein, The gas collecting cavity (111) penetrates the simulation seat (11) along the axial direction; the installation plate (18) is detachably connected between the simulation seat (11) and the optical glass cover (12), the installation hole is arranged on the installation plate (18); the support plate (19) is detachably connected to one end of the simulation seat (11) away from the installation plate (18) along the axial direction, and the air inlet hole (112) is arranged on the support plate (19); the secondary vortex generator (13) is detachably connected in the installation hole; Before the flow field measurement is performed, according to the type of the vortex generator for the flow field test, the sealing and cooperation of vortex generators of different types and structures can be realized by replacing the nozzle head (15), the nozzle sleeve (16) and the installation plate (18) with corresponding installation holes; or according to the number of vortex generators for the flow field test, the flow field measurement can be realized by replacing the installation plate (18) with corresponding installation holes, the support plate (19) with corresponding air inlet holes (112) and increasing or decreasing the corresponding number of the spring (17), the nozzle head (15) and the nozzle sleeve (16).

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