Internal flow field peeping type PIV (particle image velocimetry) testing device and method for turbomachinery

Abstract

The invention relates to the technical field of PIV (particle image velocimetry) flow field testing devices, in particular to an internal peeping type PIV testing device and method for an internal flow field of turbomachinery, and the device comprises the turbomachinery, a testing assembly and a connecting assembly. The testing assembly comprises a lighting mechanism, a camera shooting mechanism, a laser mounting pipe arranged on the air inlet pipe, a mounting base arranged on the laser mounting pipe and a camera shooting mounting mechanism arranged on the air inlet pipe, and the connecting assembly comprises an inserting mechanism arranged on the laser mounting pipe and a connecting mechanism arranged on the camera shooting mechanism. Through the arrangement of the mounting base and the camera mounting mechanism, a laser light source emitter and a camera are quickly mounted, the camera can adapt to various special-shaped shells such as volutes, the angle of a sheet light source emitted by the laser light source emitter is quickly adjusted through the arrangement of a rotating pipe, and the angle of the sheet light source is adjusted through the arrangement of a connecting mechanism and an inserting mechanism. And the sheet light source emitted by the laser light source emitter is quickly perpendicular to the shooting direction of the camera mechanism again.

Description

Technical Field

[0001] The present invention relates to the technical field of PIV flow field testing devices, and specifically to an endoscopic PIV testing device and method for the internal flow field of a turbomachine. Background Technique

[0002] Particle Image Velocimetry (PIV) is a non-contact flow measurement method based on optical imaging. By spreading micron-scale tracer particles (such as titanium dioxide, aluminum powder, etc.) in the flow field, using a pulsed laser sheet light source to irradiate the area to be measured, and using a high-speed camera to record the continuous exposure images of the particles within a very short time interval. By analyzing the displacement of the particles in the image through cross-correlation algorithm or particle tracking method, combined with the time interval and optical calibration parameters, the velocity vector in the flow field can be calculated, and further physical quantities such as vorticity field and pressure field can be derived.

[0003] An endoscopic PIV testing device for the axial flow velocity field test of a water pump provided in the publication number CN113325195B, characterized in that it includes a test housing module and an endoscope system. Among them, the test housing module includes a pump impeller sleeve, a base, and a sealing mechanism, and the endoscope system includes a camera module and a sheet light source module. Based on the opaque impeller sleeve of the water pump, the present invention imports the endoscope system into the impeller sleeve and combines it with the PIV test camera and sheet light source by welding a Φ38 base, drilling a Φ10 through hole, and assembling a sealing mechanism, and directly measures the axial velocity field of the pump.

[0004] However, when the above-mentioned endoscopic PIV testing device for the axial flow velocity field test of a water pump is in use, the laser emission device and the camera are inserted through the horizontal base and the vertical base provided on the housing module, and only the internal flow field of the impeller at a single angle can be photographed, and it is inconvenient to quickly change the shooting angle. Summary of the Invention

[0005] The purpose of the present invention is to provide an endoscopic PIV testing device and method for the internal flow field of a turbomachine to solve the problems raised in the above background technique.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: On the one hand, an endoscopic PIV testing device for the internal flow field of a turbomachine is provided, including: A turbomachine, the turbomachine includes a housing, an impeller provided in the housing, an air outlet pipe and an air inlet pipe provided on the housing, and an air extraction motor provided on the housing and connected to the impeller; Testing component, the testing component includes a lighting mechanism and a camera mechanism, a laser installation tube arranged on the intake pipe, an installation base arranged on the laser installation tube, and a plurality of camera installation mechanisms arranged on the intake pipe. A tracer particle inlet is arranged on the laser installation tube; Connection component, the connection component includes a plugging mechanism arranged on the laser installation tube and a connection mechanism arranged on the camera mechanism. The symmetric center plane of the installation base and the symmetric center plane of the plugging mechanism are perpendicular to each other. The laser installation tube includes a fixed tube arranged on the intake pipe, an annular sliding rail inserted on the fixed tube, and a rotating tube arranged on the annular sliding rail. The lighting mechanism includes a laser light source emitter and a fixed head arranged on the laser light source emitter.

[0007] Preferably, the installation base includes a base tube inserted on the rotating tube, a positioning installation tube arranged in the base tube, through holes, displacement grooves and sliding grooves arranged on the positioning installation tube, a pressing slider arranged in the sliding groove, a downward pressing groove arranged on the pressing slider, a limiting groove arranged on the displacement groove wall and surrounding the through hole, a limiting baffle arranged on the pressing slider, an annular airbag arranged on the displacement groove wall and located in the limiting baffle, a return spring arranged between the pressing slider and the displacement groove wall, a movable locking tongue inserted in the positioning installation tube, a guiding pull rod arranged on the movable locking tongue and inserted on the base tube, a locking spring with two ends respectively arranged between the base tube and the movable locking tongue, and a bracket arranged on the rotating tube.

[0008] Preferably, the laser light source emitter is arranged in the through hole, so that the fixed head cooperates with the downward pressing groove to push the pressing slider to move, so that the limiting baffle cooperates with the limiting groove, the annular airbag fits the laser light source emitter, the movable locking tongue cooperates with the fixed head, and the fixed head is located between the downward pressing groove and the movable locking tongue.

[0009] Preferably, the camera mechanism includes a camera, a probe arranged on the camera, an insertion ring arranged on the probe, insertion pieces arranged on the insertion ring, positioning holes arranged on the insertion pieces, and a rubber plug arranged on the insertion ring. The front diameter of the rubber plug is smaller than the rear diameter. The camera installation mechanism includes an outer tube shell inserted on the intake pipe, an inner tube shell arranged in the outer tube shell, a slot arranged on the inner tube shell, a rotating ring arranged on the inner tube shell, and an insertion rod arranged on the rotating ring.

[0010] Preferably, the rubber plug cooperates with the inner tube shell, and the insertion piece cooperates with the slot. The rotating ring is rotatably connected to the inner tube, so that the insertion rod is arranged in the positioning hole.

[0011] Preferably, the plug-in mechanism includes a plug-in base block arranged on the rotating tube, a plug-in guide rail arranged on the plug-in base block, a door-shaped plug-in plate arranged on the plug-in guide rail, a connecting plate arranged on the door-shaped plug-in plate, and a connecting hole arranged on the connecting plate.

[0012] Preferably, the connecting mechanism includes a positioning plate arranged on the outer tube shell, a positioning groove arranged on the positioning plate, a positioning guide rod inserted on the wall of the positioning groove, and a positioning spring sleeved on the positioning guide rod.

[0013] Preferably, the rotating tube is rotatably connected to the fixed tube, the connecting plate is arranged in the positioning groove, the positioning guide rod is arranged in the connecting hole, and the light curtain emitted by the laser light source emitter is perpendicular to the shooting direction of the camera.

[0014] On the other hand, a testing method of an endoscopic PIV testing device for an internal flow field of a turbomachinery based on any one of the above items is also provided: S1: placing the laser light source emitter on the bracket, inserting the laser light source emitter into the through hole, inserting the fixing head into the lower pressing groove, and pushing the pressing slider to move, inserting the limit baffle into the limit groove, and squeezing the annular airbag to make the annular airbag fit the laser light source emitter, when the limit baffle contacts the bottom wall of the limit groove, the movable locking tongue moves to abut against the fixing head under the push of the locking spring, and fixes the laser light source emitter; S2: inserting the rubber plug into the inner tube shell and the inserting piece into the slot, so that the rubber plug plugs the inner tube shell and then rotating the rotating ring to insert the inserting rod into the positioning hole to fix the probe; S3: Rotate the rotating tube to align the connecting plate with the positioning groove on the outer tube shell on which the probe is installed; S4: After pulling the positioning guide rod, move the gate-shaped plug plate to insert the connecting plate into the positioning groove, insert the positioning guide rod into the connecting hole, and make the light curtain emitted by the laser light source emitter perpendicular to the shooting direction of the camera; S5: starting the air extraction motor, the tracer particles are sucked into the housing from the tracer particle inlet, the tracer particles follow the air into the air inlet pipe and are discharged from the air outlet pipe, and the camera takes pictures; S5: stop the vacuum motor, rotate the rotating ring in the opposite direction, remove the probe, repeat S2, and insert the probe into another inner tube shell; S6: Repeat S3-S5 to allow the camera to capture the internal flow field at another viewing angle.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: Through the settings of the installation base and the camera installation mechanism, the present invention can quickly install the laser light source emitter and the camera, and can adapt to various special-shaped shells such as volute casings. Through the setting of the rotating tube, the angle of the sheet light source emitted by the laser light source emitter can be quickly adjusted. And through the settings of the connection mechanism and the plugging mechanism, the sheet light source emitted by the laser light source emitter can be quickly made perpendicular to the shooting direction of the camera mechanism again. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a schematic cross-sectional structural diagram of the present invention; Figure 3 is a schematic structural diagram of the installation base of the present invention; Figure 4 is a schematic cross-sectional structural diagram of the installation base of the present invention with the base tube hidden; Figure 5 is a schematic cross-sectional structural diagram of the positioning installation tube and the pressing slider of the present invention; Figure 6 is a schematic cross-sectional structural diagram of the positioning installation tube of the present invention; Figure 7 is a schematic structural diagram of the movable locking tongue of the present invention; Figure 8 is a diagram showing the positional relationship between the laser light source emitter and the pressing slider of the present invention; Figure 9 is a schematic structural diagram of the connection assembly of the present invention; Figure 10 is a schematic structural diagram of the outer tube shell of the present invention; Figure 11 is a diagram showing the positional relationship between the inner tube shell and the probe of the present invention; Figure 12 is a schematic structural diagram of the probe and the rotating ring of the present invention; Figure 13 is a schematic structural diagram of the plugging mechanism of the present invention.

[0017] In the figure: 1. Outer shell; 2. Impeller; 3. Exhaust pipe; 4. Intake pipe; 5. Exhaust motor; 6. Tracer particle inlet; 7. Fixed pipe; 8. Annular slide rail; 9. Rotating pipe; 10. Laser light source emitter; 11. Fixed head; 12. Base pipe; 13. Positioning and installation pipe; 14. Through hole; 15. Displacement groove; 16. Slide groove; 17. Pressing slider; 18. Pressing down groove; 19. Limiting groove; 20. Limiting baffle; 21. Annular airbag; 22. Reset spring; 23. Movable locking tongue; 24. Guide pull rod; 25. Locking spring; 26. Bracket; 27. Camera; 28. Probe; 29. Insert ring; 30. Insert piece; 31. Positioning hole; 32. Rubber plug; 33. Outer pipe shell; 34. Inner pipe shell; 35. Slot; 36. Rotating ring; 37. Insert rod; 38. Inserting base block; 39. Inserting guide rail; 40. Gate-shaped insertion plate; 41. Connecting plate; 42. Connecting hole; 43. Positioning plate; 44. Positioning groove; 45. Positioning guide rod; 46. Positioning spring. Detailed implementation manner

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] Please refer to Figures 1 to 13 , the present invention provides a technical solution: An endoscopic PIV test device for the internal flow field of an impeller machine, comprising: An impeller machine, and the impeller machine can be selected from various machines with an impeller 2 such as a vacuum compressor. The impeller machine includes an outer shell 1, an impeller 2, an exhaust pipe 3, an intake pipe 4, and an exhaust motor 5. The impeller 2 is arranged inside the outer shell 1, and the impeller 2 is rotationally connected to the outer shell 1 by means of arranging bearings and connecting shafts, etc. The exhaust pipe 3 and the intake pipe 4 are arranged on the outer shell 1, the exhaust pipe 3 is fixedly connected to the outer shell 1 by means of welding, etc., the intake pipe 4 is fixedly connected to the outer shell 1 by means of welding, etc., the exhaust motor 5 is arranged on the outer shell 1 and is connected to the impeller 2, the exhaust motor 5 is fixedly connected to the outer shell 1 by means of arranging bolts, etc., and the exhaust motor 5 is fixedly connected to the connecting shaft of the impeller 2 by means of arranging a coupling, etc.

[0020] Testing component, the testing component includes a lighting mechanism and a camera mechanism, a laser installation tube provided on the intake pipe 4, a mounting base provided on the laser installation tube, and a camera mounting mechanism provided on the intake pipe 4. A tracer particle inlet 6 is provided on the laser installation tube. The laser installation tube includes a fixed tube 7, an annular slide rail 8, and a rotating tube 9. The fixed tube 7 is fixedly connected to the intake pipe 4 by means of bolts or the like. The rotating tube 9 is arranged on the annular slide rail 8, and the rotating tube 9 is rotatably connected to the fixed tube 7 through the annular slide rail 8. The tracer particle inlet 6 is provided on the fixed tube 7, and the tracer particle inlet 6 is fixedly connected to the fixed tube 7 by means of welding or the like. The tracer particle inlet 6 is communicated with an external tracer particle storage chamber so that the gas mixed with tracer particles enters the housing 1. The lighting mechanism includes a laser light source emitter 10 and a fixed head 11 provided on the laser light source emitter 10. The fixed head 11 is fixedly connected to the laser light source emitter 10 by means of threaded pins or adhesives. The laser light source emitter 10 is used to emit a sheet light source.

[0021] The installation base includes a base pipe 12, a positioning and installation pipe 13, a through hole 14, a displacement groove 15, a sliding groove 16, a pressing slider 17, a downward pressing groove 18, a limiting groove 19, a limiting baffle 20, a return spring 22, a moving locking tongue 23, a guiding pull rod 24, a locking spring 25, and a bracket 26. The base pipe 12 is inserted into the rotating pipe 9, and the base pipe 12 is fixedly connected to the rotating pipe 9 by welding or other means. The axis of the base pipe 12 is aligned with the impeller 2. The positioning and installation pipe 13 is arranged inside the base pipe 12, and the positioning and installation pipe 13 is fixedly connected to the base pipe 12 by welding or other means. The through hole 14, the displacement groove 15, and the sliding groove 16 are opened on the positioning and installation pipe 13. The pressing slider 17 is arranged in the sliding groove 16, and the pressing slider 17 is movably connected to the sliding groove 16. The downward pressing groove 18 is opened on the pressing slider 17, and an empty groove corresponding to the through hole 14 is opened on the pressing slider 17. The limiting groove 19 is opened on the bottom wall of the displacement groove 15 and surrounds the through hole 14. The limiting groove 19 is circular. The limiting baffle 20 is arranged on the pressing slider 17, and the limiting baffle 20 is fixedly connected to the pressing slider 17 by welding or other means. The annular airbag 21 is arranged on the bottom wall of the displacement groove 15 and is surrounded by the limiting baffle 20. The limiting baffle 20 is used to prevent the annular airbag 21 from expanding towards the return spring 22 and interfering with the operation of the return spring 22. The inner wall of the limiting baffle 20 is smooth and always surrounds the annular airbag 21. The annular airbag 21 is fixedly connected to the groove wall of the displacement groove 15 by gluing or other means. The size of the annular airbag 21 can be reasonably selected according to the actual use situation, and it is necessary to avoid selecting an annular airbag 21 with too large a size, so as to avoid excessive friction between the annular airbag 21 and the limiting baffle 20. The return spring 22 is arranged between the pressing slider 17 and the wall of the displacement groove 15. One end of the return spring 22 is fixedly connected to the pressing slider 17 by welding or other means, and the other end of the return spring 22 is fixedly connected to the bottom wall of the displacement groove 15 by welding or other means. The moving locking tongue 23 is inserted into the positioning and installation pipe 13, and the moving locking tongue 23 is movably connected to the side wall of the sliding groove 16 of the positioning and installation pipe 13. The guiding pull rod 24 is arranged on the moving locking tongue 23 and is inserted into the base pipe 12. The guiding pull rod 24 is fixedly connected to the moving locking tongue 23 by welding or other means, and the guiding pull rod 24 is movably connected to the base pipe 12. The two ends of the locking spring 25 are respectively arranged between the base pipe 12 and the moving locking tongue 23. One end of the locking spring 25 is fixedly connected to the inner wall of the base pipe 12 by welding or other means, and the other end of the locking spring 25 is fixedly connected to the moving locking tongue 23 by welding or other means. The bracket 26 is arranged on the rotating pipe 9, and the bracket 26 is fixedly connected to the rotating pipe 9 by welding or other means. When the laser light source emitter 10 is placed on the bracket 26, the laser light source emitter 10 is inserted into the through hole 14. The guiding pull rod 24 is pulled to move the moving locking tongue 23 towards the positioning and installation pipe 13. The fixing head 11 is inserted into the downward pressing groove 18, and the pressing slider 17 is pushed to move, so that the limiting baffle 20 is inserted into the limiting groove 19, and the pressing slider 17 presses the annular airbag 21 to cause the annular airbag 21 to deform.Fit the annular airbag 21 to the laser light source emitter 10. When the limit baffle 20 contacts the bottom wall of the limit groove 19, the moving lock tongue 23 moves under the push of the locking spring 25 to abut against the fixed head 11, fixing the laser light source emitter 10. Pull the guiding pull rod 24, and the return spring 22 pushes the pressing slider 17 back to its original position, releasing the fixation of the laser light source emitter 10.

[0022] The camera mechanism includes a camera 27, a probe 28, an insertion ring 29, an insertion piece 30, a positioning hole 31, and a rubber plug 32. The probe 28 is rope-shaped and is connected to the camera 27 through an interface. Appropriate cameras 27 and probes 28 can be selected according to actual situations to meet functions such as focusing and autofocus. The insertion ring 29 is arranged on the probe 28 and is fixedly connected to the probe 28 by means such as gluing or setting threaded pins. The insertion depth of the probe 28 in the inner tube shell 34 is controlled by adjusting the position of the insertion ring 29 on the probe 28, and thus the distance between the probe 28 and the sheet light source is controlled. Similarly, by adjusting the position of the fixed head 11 on the laser light source emitter 10, the insertion depth of the laser light source emitter 10 is controlled. The insertion piece 30 is arranged on the insertion ring 29 and is fixedly connected to the insertion ring 29 by means such as integral molding. The positioning hole 31 is opened on the insertion piece 30. The rubber plug 32 is arranged on the insertion ring 29 and is fixedly connected to the insertion ring 29 by means such as gluing. The front diameter of the rubber plug 32 is smaller than the rear diameter.

[0023] The camera mounting mechanism includes an outer tube shell 33, an inner tube shell 34, a slot 35, a rotating ring 36, and an insertion rod 37. The outer tube shell 33 is inserted into the air inlet pipe 4 and is fixedly connected to the air inlet pipe 4 by means such as welding. The inner tube shell 34 is arranged in the outer tube shell 33 and is fixedly connected to the outer tube shell 33 by means such as welding. The slot 35 is opened on the inner tube shell 34. The rotating ring 36 is sleeved on the inner tube shell 34 and is rotatably connected to the inner tube shell 34. The insertion rod 37 is arranged on the rotating ring 36 and is connected to the rotating ring 36 by means such as welding. The rubber plug 32 is used to be inserted into the inner tube shell 34, and the insertion piece 30 is inserted into the slot 35. After the rubber plug 32 plugs the inner tube shell 34, rotate the rotating ring 36 to make the insertion rod 37 insert into the positioning hole 31 to fix the probe 28. In the inner tube shell 34 where the probe 28 is not inserted, a preset plugging block with the same structure as the probe 28 can be inserted to prevent air leakage in the inner tube shell 34.

[0024] Connecting component, the connecting component includes a plugging mechanism arranged on the laser installation tube and a connecting mechanism arranged on the camera mechanism. The symmetry center plane of the installation base and the symmetry center plane of the plugging mechanism are perpendicular to each other. The plugging mechanism includes a plugging base block 38, a plugging guide rail 39, a U-shaped plug board 40, a connecting plate 41 and a connecting hole 42. The plugging base block 38 is arranged on the rotating tube 9, and the plugging base block 38 is fixedly connected to the side wall of the rotating tube 9 by welding or other means. The plugging guide rail 39 is arranged on the plugging base block 38, the U-shaped plug board 40 is arranged on the plugging guide rail 39, and the U-shaped plug board 40 is movably connected to the plugging base block 38 through the plugging guide rail 39. The connecting plate 41 is arranged on the U-shaped plug board 40, and the connecting plate 41 is fixedly connected to the U-shaped plug board 40 by integral molding or other means. The connecting hole 42 is arranged on the connecting plate 41.

[0025] The connecting mechanism includes a positioning plate 43, a positioning groove 44, a positioning guide rod 45 and a positioning spring 46. The positioning plate 43 is arranged on the outer tube shell 33, and the positioning plate 43 is fixedly connected to the outer tube shell 33 by integral molding or other means. The positioning groove 44 is arranged on the positioning plate 43, the positioning guide rod 45 is inserted on the side wall of the positioning groove 44, and the positioning guide rod 45 is movably connected to the side wall of the positioning groove 44. The positioning spring 46 is sleeved on the positioning guide rod 45, one end of the positioning spring 46 is fixedly connected to the positioning guide rod 45 by welding or other means, and the other end of the positioning spring 46 is fixedly connected to the positioning plate 43 by welding or other means. Rotate the rotating tube 9 to align the connecting plate 41 with the positioning groove 44 on the outer tube shell 33 where the probe 28 is installed. After pulling the positioning guide rod 45, move the U-shaped plug board 40 to insert the connecting plate 41 into the positioning groove 44, insert the positioning guide rod 45 into the connecting hole 42, and make the light curtain emitted by the laser light source emitter 10 perpendicular to the shooting direction of the camera 27.

[0026] Working principle: When in use, place the laser light source transmitter 10 on the bracket 26, insert the laser light source transmitter 10 into the through hole 14, pull the guide pull rod 24, insert the fixed head 11 into the lower pressing groove 18, and push the pressing slider 17 to move, so that the limit baffle 20 is inserted into the limit groove 19, and squeeze the annular airbag 21, so that the annular airbag 21 fits the laser light source transmitter 10. When the limit baffle 20 contacts the bottom wall of the limit groove 19, the movable lock tongue 23 moves to abut against the fixed head 11 under the push of the locking spring 25, and the laser light source transmitter 10 is fixed. The rubber plug 32 is inserted into the inner tube shell 34, and the insert piece 30 is inserted into the slot 35. After the rubber plug 32 plugs the inner tube shell 34, the rotating ring 36 is rotated to insert the insert rod 37 into the positioning hole 31. The probe 28 is fixed, and the rotating tube 9 is rotated to align the connecting plate 41 with the positioning groove 44 on the outer tube shell 33 where the probe 28 is installed. After pulling the positioning guide rod 45, the door-shaped plug plate 40 is moved to insert the connecting plate 41 into the positioning groove 44, and the positioning guide rod 45 is inserted into the connecting hole 42, so that the light curtain emitted by the laser light source emitter 10 and the shooting direction of the camera 27 are aligned. The vacuum motor 5 is turned vertically, and the tracer particles are sucked into the housing 1 from the tracer particle inlet 6, so that the tracer particles follow the air into the air inlet pipe 4 and are discharged from the air outlet pipe 3. The camera 27 takes pictures, and the vacuum motor 5 is stopped. After the rotating ring 36 is rotated in the opposite direction, the probe 28 is removed, and the rubber plug 32 is inserted into the inner tube shell 34 again, and the insert 30 is inserted into the slot 35. After the rubber plug 32 plugs the inner tube shell 34, the rotating ring 36 is rotated to insert the insert rod 37 into the positioning hole 31, so that the probe 28 is fixed again, and the probe 28 is inserted into another inner tube shell 34. In the process, the rotating tube 9 is rotated again to align the connecting plate 41 with the positioning groove 44 on the outer tube shell 33 on which the probe 28 is installed, and after pulling the positioning guide rod 45, the door-shaped plug plate 40 is moved to insert the connecting plate 41 into the positioning groove 44, and the positioning guide rod 45 into the connecting hole 42, so that the light curtain emitted by the laser light source emitter 10 and the shooting direction of the camera 27 are perpendicular again, and the exhaust motor 5 is restarted, and the tracer particles are sucked into the outer shell 1 from the tracer particle inlet 6, so that the tracer particles follow the air into the air inlet pipe 4 and are discharged from the air outlet pipe 3, and the camera 27 takes pictures.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An endoscopic PIV test device for the internal flow field of a turbomachine, characterized in that, Comprising: An impeller machine, which includes a housing, an impeller arranged inside the housing, an air outlet pipe and an air inlet pipe arranged on the housing, and an air extraction motor arranged on the housing and connected to the impeller; A test component, which includes a polishing mechanism and a camera mechanism, a laser installation pipe arranged on the air inlet pipe, a mounting base arranged on the laser installation pipe, and a plurality of camera mounting mechanisms arranged on the air inlet pipe. A tracer particle inlet is arranged on the laser installation pipe; A connection component, which includes a plugging mechanism arranged on the laser installation pipe and a connection mechanism arranged on the camera mechanism. The symmetric center planes of the mounting base and the plugging mechanism are perpendicular to each other. The laser installation pipe includes a fixed pipe arranged on the air inlet pipe, an annular slide rail inserted on the fixed pipe, and a rotating pipe arranged on the annular slide rail. The polishing mechanism includes a laser light source emitter and a fixed head arranged on the laser light source emitter.

2. The endoscopic PIV test device for the internal flow field of an impeller machine according to claim 1, wherein: The mounting base includes a base pipe inserted on the rotating pipe, a positioning installation pipe arranged inside the base pipe, through holes, displacement grooves and sliding grooves arranged on the positioning installation pipe, a pressing slider arranged in the sliding groove, a downward pressing groove arranged on the pressing slider, a limiting groove arranged on the displacement groove wall and surrounding the through hole, a limiting baffle arranged on the pressing slider, an annular air bag arranged on the displacement groove wall and located in the limiting baffle, a reset spring arranged between the pressing slider and the displacement groove wall, a movable locking tongue inserted in the positioning installation pipe, a guiding pull rod arranged on the movable locking tongue and inserted on the base pipe, a locking spring with two ends respectively arranged between the base pipe and the movable locking tongue, and a bracket arranged on the rotating pipe.

3. The endoscope PIV test device for the internal flow field of an impeller machine according to claim 2, wherein: The laser light source emitter is arranged in the through hole, so that the fixed head cooperates with the downward pressing groove to push the pressing slider to move, so that the limiting baffle cooperates with the limiting groove, the annular air bag fits the laser light source emitter, the movable locking tongue cooperates with the fixed head, and the fixed head is located between the downward pressing groove and the movable locking tongue.

4. An endoscope PIV test device for the internal flow field of an impeller machine according to claim 3, characterized in that: The camera mechanism includes a camera, a probe arranged on the camera, an insertion ring arranged on the probe, insertion pieces arranged on the insertion ring, positioning holes arranged on the insertion pieces, and a rubber plug arranged on the insertion ring. The front diameter of the rubber plug is smaller than the rear diameter. The camera mounting mechanism includes an outer tube shell inserted on the air inlet pipe, an inner tube shell arranged in the outer tube shell, a slot arranged on the inner tube shell, a rotating ring arranged on the inner tube shell, and an insertion rod arranged on the rotating ring.

5. The endoscopic PIV test device for the internal flow field of an impeller machine according to claim 4, wherein: The rubber plug cooperates with the inner tube shell, and the insertion piece cooperates with the slot. The rotating ring is rotatably connected to the inner tube, so that the insertion rod is arranged in the positioning hole.

6. The endoscopic PIV test device for the internal flow field of an impeller machine according to claim 4, characterized in that: The plugging mechanism includes a plugging base block arranged on the rotating pipe, a plugging guide rail arranged on the plugging base block, a U-shaped plug board arranged on the plugging guide rail, a connecting plate arranged on the U-shaped plug board, and a connecting hole arranged on the connecting plate.

7. An endoscopic PIV test device for the internal flow field of an impeller machine according to claim 6, characterized in that: The connecting mechanism includes a positioning plate provided on the outer casing, a positioning groove provided on the positioning plate, a positioning guide rod inserted on the wall of the positioning groove, and a positioning spring sleeved on the positioning guide rod.

8. An endoscopic PIV test device for the internal flow field of a turbomachine according to claim 7, characterized in that: The rotating tube is rotatably connected to the fixed tube. The connecting plate is disposed in the positioning groove. The positioning guide rod is disposed in the connecting hole. The light curtain emitted by the laser light source emitter is perpendicular to the shooting direction of the camera.

9. A test method for an endoscopic PIV test device in the internal flow field of an impeller machine according to claim 8 above, characterized in that: S1: Place the laser light source emitter on the bracket, insert the laser light source emitter into the through hole, insert the fixed head into the pressing groove, and push the pressing slider to move, so that the limiting baffle is inserted into the limiting groove, and the annular airbag is squeezed, so that the annular airbag fits against the laser light source emitter. When the limiting baffle contacts the bottom wall of the limiting groove, the moving locking tongue moves under the push of the locking spring to abut against the fixed head to fix the laser light source emitter; S2: Insert the rubber plug into the inner casing, and insert the insertion piece into the insertion slot. After the rubber plug plugs the inner casing, rotate the rotating ring so that the insertion rod is inserted into the positioning hole to fix the probe; S3: Rotate the rotating tube so that the connecting plate aligns with the positioning groove on the outer casing where the probe is installed; S4: Pull the positioning guide rod, then move the U-shaped insertion plate so that the connecting plate is inserted into the positioning groove, and the positioning guide rod is inserted into the connecting hole, so that the light curtain emitted by the laser light source emitter is perpendicular to the shooting direction of the camera; S5: Start the air extraction motor, and the tracer particles are drawn into the casing from the tracer particle inlet, so that the tracer particles enter from the intake pipe and are discharged from the outlet pipe along with the air, and the camera takes pictures; S5: Stop the air extraction motor, rotate the rotating ring in the reverse direction, then remove the probe, repeat S2, and insert the probe into another inner casing; S6: Repeat S3 - S5 so that the camera takes pictures of the internal flow field from another perspective.

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