Rotating hydrofoil cavitation experiment device and method

Abstract

The application relates to the technical field of water wing cavitation experiment, and discloses a rotating water wing cavitation experiment device and method, which comprises a base, a transparent water tank and a variable frequency motor controlled by a computer are arranged on the upper end left side of the base through a fixed support, a high-speed camera and a light supplement lamp connected with a computer signal are arranged on the upper end right side of the base; a rotating disc is fixed to the output end of the variable frequency motor and extends into the transparent water tank, a sealing assembly is arranged at the connection position of the rotating shaft and the transparent water tank; rotating installation pieces are arranged on the rotating disc at equal intervals, and the rotating installation pieces are used for installing water wing test pieces. The sealing assembly is matched with an external thread cylinder and a protective cover to form multiple seals, the water-tight seal of the rotating shaft and the transparent water tank is realized, the meshing position of the tooth ring and the driven gear is sealed, water body interference is reduced, rotating friction of the rotating shaft is reduced, leakage is avoided, and the operation stability of the device is improved; the water wing test piece can be quickly disassembled, the disassembly process is simplified, and the water wing test piece is convenient to replace and the device is convenient to clean.

Description

Technical Field

[0001] This invention relates to the field of hydrofoil cavitation experimental technology, specifically to a rotating hydrofoil cavitation experimental apparatus and method. Background Technology

[0002] As a core flow-through component in hydraulic and marine engineering, hydrofoils are subject to wear and corrosion over long-term use, resulting in pitting or honeycomb-like pores on their surface. Their cavitation characteristics directly determine the hydrodynamic performance, operational stability, and service life of the equipment. Therefore, cavitation testing is a key technical support for hydrofoil structural optimization. Currently, existing rotating hydrofoil cavitation testing devices suffer from poor sealing at the connection between the shaft and the water tank, leading to water leakage. Hydrofoil specimen installation and disassembly are cumbersome, requiring the removal of multiple components, which is time-consuming and labor-intensive, hindering specimen replacement and device cleaning. Furthermore, the hydrofoil angle adjustment mechanism is complex, with low adjustment precision, making it difficult to achieve simultaneous and precise angle adjustment of multiple hydrofoils. Loosening during adjustment can also affect experimental stability, failing to meet the requirements of comparative cavitation experiments at different angles of attack, thus limiting experimental efficiency and data accuracy. To address these issues, we have developed a rotating hydrofoil cavitation testing device and method. Summary of the Invention

[0003] The purpose of this invention is to provide a rotating hydrofoil cavitation experimental apparatus and method to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A rotating hydrofoil cavitation experimental device includes a base, on the upper left side of the base a transparent water tank and a computer-controlled variable frequency motor are mounted on a fixed bracket, and on the upper right side of the base a high-speed camera connected to a computer signal and a supplementary light are mounted. The rotating shaft at the output end of the variable frequency motor extends into the transparent water tank and is fixed with a rotating disc, and a sealing component is provided at the connection between the rotating shaft and the transparent water tank. Rotary mounting components are provided at equal intervals on the rotating disk. The rotating mounting components are used to install hydrofoil test specimens. An external threaded cylinder is screwed into the annular groove in the middle of the left end of the rotating disk. The left end of the external threaded cylinder is sleeved on the outside of the right end of the sealing assembly. The toothed ring sleeved on the external threaded cylinder meshes with the left end of the rotating mounting component. A protective cover is fixed to the outside of the external threaded cylinder. The protective cover is sleeved on the outside of the left end of the rotating disk. Several sets of sliding connectors arranged at equal intervals on the protective cover are slidably connected to the left end of the toothed ring.

[0005] Preferably, the transparent water tank is provided with an end cap on the top, an inlet valve is connected to the water inlet pipe on the top of the end cap, and an outlet valve is connected to the water outlet pipe on the bottom right side of the transparent water tank.

[0006] Preferably, the high-speed camera is fixed to the upper right side of the base using a mounting bracket, and the top of the mounting bracket is fixed to the fill light using a horizontal frame, while the computer is mounted on the upper part of the base using a stand.

[0007] Preferably, the rotating disk has a sleeve in the middle of the left end, and the sleeve is fitted onto the right end of the rotating shaft with a long bolt. The right end of the rotating shaft has a bolt hole for the long bolt to pass through and protrude.

[0008] Preferably, the sealing assembly includes a sleeve fitted onto the rotating shaft via the inside of the transparent water tank, an inner limiting ring seat fixed at the end of the sleeve, and an outer limiting ring seat fitted onto the sleeve after it extends out of the transparent water tank. The inner limiting ring seat has an inner bearing that is sleeved on the rotating shaft embedded inside, and the outer limiting ring seat has an outer bearing that is sleeved on the rotating shaft embedded inside. An inner sealing ring is embedded at one end of the inner limiting ring seat near the sleeve, and a sealing gasket is sleeved on the outer side of the other end of the inner limiting ring seat. The external threaded sleeve is sleeved on the outer side of the inner limiting ring seat. An outer sealing ring is embedded in the inner wall of the outer limiting ring seat; The screws on the outer limiting ring seat penetrate the side wall of the transparent water tank and are then screwed and fixed to the inner limiting ring seat.

[0009] Preferably, the right end of the rotating disk is provided with equally spaced circular inner grooves; The rotating mounting component includes a circular fixed seat disposed in a circular inner groove, a connecting shaft fixed in the middle of the circular fixed seat, and a driven gear fixed after the connecting shaft extends through and out of the rotating disk. A square through groove is provided between the circular fixed seat, the connecting shaft, and the driven gear. A bearing is also sleeved on the outside of the connecting shaft. The driven gear meshes with the ring gear.

[0010] Preferably, the hydrofoil specimen includes a hydrofoil body, a circular mounting plate fixed at the root of the hydrofoil body, and a screw rod fixed in the middle of the circular mounting plate by a square column; The square column extends through a square through slot, and a locking nut is screwed onto the screw.

[0011] Preferably, the sliding connector includes a fixed cylinder evenly spaced at the left end of the cover, a sliding rod centrally located inside the fixed cylinder, and a spring sleeved on the outside of the sliding rod inside the fixed cylinder; The toothed ring is provided with positioning cylinders at equal intervals on its left end, and a sliding joint hole is provided in the middle between the positioning cylinder and the toothed ring, and the sliding joint rod is inserted into the sliding joint hole; The positioning cylinder extends into the spring, and the right end of the spring is fixed to the left end surface of the toothed ring.

[0012] Preferably, the transparent water tank is equipped with a heating plate at the bottom, and a thermometer and a pressure gauge are also provided on the transparent water tank. The heating plate, thermometer, and pressure gauge are electrically connected to a computer.

[0013] The present invention also provides an experimental method for a rotating hydrofoil cavitation experimental device, specifically including the following steps: S1. By rotating the cover clockwise, the external threaded cylinder is further screwed into the annular groove. At this time, the sliding connector on the cover will drive the toothed ring to rotate, and the toothed ring will drive the rotating mounting part and the hydrofoil specimen installed on the rotating mounting part to rotate, thereby adjusting the angle of the hydrofoil specimen. S2. The computer controls the operation of the variable frequency motor, which drives the hydrofoil specimen to rotate through the rotating disk. Then, the computer controls the high-speed camera to continuously collect images and capture the dynamic evolution process of cavitation of the hydrofoil specimen under rotating conditions from initiation, development, separation, detachment to collapse in real time. S3: High-definition image data captured by the high-speed camera is transmitted to the computer in real time for lossless storage. S4. Rotate the cover counterclockwise until it leaves space behind the rotating disc, then remove the hydrofoil specimen.

[0014] Compared with the prior art, the beneficial effects of the present invention are: the sealing component of the present invention, together with the external threaded cylinder and the protective cover, forms a multi-layer seal, which not only achieves a watertight seal between the rotating shaft and the transparent water tank, but also seals the meshing point between the gear ring and the driven gear, reduces water interference, reduces the rotational friction of the rotating shaft, eliminates leakage, and improves the operational stability of the device.

[0015] This invention utilizes a square column and a square through slot, with a screw and a locking nut for secure fastening. Rotating the cover counterclockwise allows for the provision of operating space, facilitating quick disassembly of the hydrofoil specimen and simplifying the assembly and disassembly process. This also makes it easier to replace the hydrofoil specimen and clean the device. Furthermore, the rotating cover uses a sliding connector to drive a gear ring and a driven gear, enabling simultaneous angle adjustment of multiple hydrofoils. A spring ensures tight engagement, precise and convenient adjustment, meeting the needs of comparative experiments with different angles of attack and improving experimental efficiency. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the entire invention; Figure 2 This is a three-dimensional structural diagram of the end cap of the present invention after disassembly; Figure 3 This is an exploded structural diagram of the sealing component and the rotating shaft assembly of the present invention; Figure 4 For the present invention Figure 3 A structural diagram from another perspective; Figure 5 This is a three-dimensional structural diagram of the assembly of the sealing component, rotating shaft, and transparent water tank of the present invention; Figure 6 This is a cross-sectional structural diagram of the assembly of the sealing component, rotating shaft, and transparent water tank of the present invention; Figure 7 This is an exploded structural diagram of the assembly of the rotating shaft, cover, gear ring, rotating disk and hydrofoil of the present invention; Figure 8 This is a schematic diagram of the hydrofoil prototype of the present invention; Figure 9 This is a cross-sectional structural diagram of the assembly of the rotating disk and the rotating mounting component of the present invention. Figure 10 This is a cross-sectional structural schematic diagram of the assembly of the protective cover, external threaded cylinder and sliding connector of the present invention; Figure 11 For the present invention Figure 7 A structural diagram from another perspective; Figure 12 This is a cross-sectional structural diagram of the assembly of the rotating shaft, sealing component, transparent water tank, external threaded cylinder and rotating disk of the present invention. Figure 13 This is a cross-sectional structural diagram of the assembly of the sealing component, cover, external threaded cylinder and rotating disk of the present invention. Figure 14 This is a cross-sectional view of the hydrofoil specimen during disassembly according to the present invention. Figure 15 This is a cross-sectional view of the hydrofoil specimen after the angle of the present invention has been adjusted.

[0017] In the diagram: 1. Base; 2. Sealing assembly; 201. Outer limiting ring seat; 202. Outer sealing ring; 203. Outer bearing; 204. Inner limiting ring seat; 205. Sealing gasket; 206. Inner bearing; 207. Screw; 208. Inner sealing ring; 209. Sleeve; 3. Motor base; 4. Variable frequency motor; 5. Rotating shaft; 6. Fixed bracket; 7. Transparent water tank; 8. Mounting bracket; 9. Stand; 10. Computer; 11. High-speed camera; 12. Horizontal frame; 13. Fill light; 14. End cap; 15. Inlet valve; 16. Outlet... 17. Waterfoil body; 18. Circular mounting plate; 19. Rotating disc; 20. Protective cover; 21. Bolt hole; 22. Locking nut; 23. Long bolt; 24. Gear ring; 25. Square column; 26. Screw; 27. Annular groove; 28. Circular inner groove; 29. ​​Circular fixing seat; 30. Square through groove; 31. Connecting shaft; 32. Driven gear; 33. Sleeve sleeve; 34. Bearing; 35. External threaded sleeve; 36. Fixing sleeve; 37. Spring; 38. Sliding rod; 39. Positioning sleeve; 40. Heating plate. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example: Please see Figures 1-15 The present invention provides a technical solution: A rotating hydrofoil cavitation experimental device includes a base 1. A transparent water tank 7 and a variable frequency motor 4 controlled by a computer 10 are mounted on the upper left side of the base 1 using a fixed bracket 6. The motor base 3 at the bottom of the variable frequency motor 4 is mounted on the upper end of the fixed bracket 6. The transparent water tank 7 is provided with an end cap 14 on the top. An inlet valve 15 is connected to the water inlet pipe on the top of the end cap 14. An outlet valve 16 is connected to the water outlet pipe on the bottom right side of the transparent water tank 7.

[0020] The experimental water and environmental parameters can be precisely controlled. The transparent water tank 7 is equipped with an inlet pipe with an inlet valve 15 at the top and an outlet valve 16 at the bottom. The two sets of valves allow for convenient filling, draining, and water replacement operations inside the tank. The transparent water tank 7 is equipped with a heating plate 40 at the bottom and a thermometer and pressure gauge on top. The heating plate 40, thermometer, and pressure gauge are electrically connected to a computer 10, which can monitor the water temperature and pressure parameters inside the transparent water tank 7 in real time and precisely control the water temperature through the heating plate 40. The system adjusts the saturated vapor pressure of the water to simulate cavitation generation conditions under different environmental parameters. Through a closed-loop system of heating plate 40 and thermometer, the power of heating plate 40 is adjusted to 300W, and the flow field temperature is monitored in real time. When the temperature reaches 25℃, heating plate 40 automatically enters constant temperature mode to maintain the flow field temperature at 25℃±0.2℃. The flow field pressure is monitored in real time by pressure gauge, and the inlet valve 15 is slowly and slightly opened and closed to accurately regulate the flow field pressure to 0.3MPa±0.01MPa and keep it stable.

[0021] A high-speed camera 11 and a supplementary light 13, connected to the computer 10, are installed on the upper right side of the base 1. During use, the computer 10 adjusts the brightness of the supplementary light 13 to 80%, and the illumination angle is adjusted to ensure no shadows or reflections in the hydrofoil specimen observation area, forming a uniform illumination field. The high-speed camera 11 is adjusted to a resolution of 1280×1024 pixels, a frame rate of 80,000 frames per second, and a focus to clearly focus on the hydrofoil specimen. The image storage path and acquisition trigger logic are set in the computer 10. The rotating shaft 5 at the output end of the variable frequency motor 4 extends into the transparent water tank 7 and is fixed with a rotating disc 19. A sealing component 2 is provided at the connection between the rotating shaft 5 and the transparent water tank 7. The sealing component 2 includes components that are sleeved on the rotating shaft 5 through the inside of the transparent water tank 7. The sleeve 209, the inner limiting ring seat 204 fixed at the end of the sleeve 209, and the outer limiting ring seat 201 sleeved after the sleeve 209 extends out of the transparent water tank 7 are all included. The inner limiting ring seat 204 has an inner bearing 206 sleeved on the rotating shaft 5, and the outer limiting ring seat 201 has an outer bearing 203 sleeved on the rotating shaft 5. The inner limiting ring seat 204 has an inner sealing ring 208 embedded at one end near the sleeve 209, and a sealing gasket 205 sleeved on the other side of the inner limiting ring seat 204. The external threaded cylinder 35 is sleeved on the outside of the inner limiting ring seat 204. The outer sealing ring 202 is embedded in the inner wall of the outer limiting ring seat 201, and the screw 207 on the outer limiting ring seat 201 passes through the side wall of the transparent water tank 7 and is screwed and fixed to the inner limiting ring seat 204.

[0022] A sealing component 2 is installed at the connection point where the rotating shaft 5 passes through the transparent water tank 7 to prevent water leakage. The sealing component 2 is mainly composed of a sleeve 209, combined with an inner limiting ring seat 204 and an outer limiting ring seat 201. The friction loss of the rotating shaft 5 at high speed is reduced by the inner bearing 206 and the outer bearing 203. The inner sealing ring 208, the sealing gasket 205, and the outer sealing ring 202 form a multi-seal structure. The inner limiting ring seat 204 and the outer limiting ring seat 201 are locked and fixed with screws 207, which effectively improves the water tightness and operational stability of the device.

[0023] Rotating mounting parts are provided at equal intervals on the rotating disk 19. The rotating mounting parts are used to install hydrofoil test specimens. An external threaded cylinder 35 is screwed into the annular groove 27 in the middle of the left end of the rotating disk 19. The left end of the external threaded cylinder 35 is sleeved on the outside of the right end of the sealing assembly 2. The toothed ring 24 sleeved on the external threaded cylinder 35 meshes with the left end of the rotating mounting part. A protective cover 20 is fixed on the outside of the external threaded cylinder 35. The protective cover 20 is sleeved on the outside of the left end of the rotating disk 19. Several sets of sliding connectors are provided at equal intervals on the protective cover 20 and are slidably connected to the left end of the toothed ring 24.

[0024] During the experiment, such as Figure 12 and Figure 13As shown, the external threaded cylinder 35 and the cover 20 together form a seal for the space between the inner limiting ring seat 204 and the rotating disk 19, which can further improve the sealing performance at the connection between the sealing assembly 2 and the rotating shaft 5, while also ensuring the seal at the meshing point between the driven gear 32 and the gear ring 24.

[0025] like Figure 15 As shown, by rotating the cover 20 clockwise, the sliding connector inside the cover 20 moves synchronously. The sliding rod 38 of the sliding connector is inserted into the sliding hole of the positioning cylinder 39 at the left end of the toothed ring 24. The rotation of the cover 20 can smoothly drive the toothed ring 24 to rotate synchronously. The toothed ring 24 then drives the rotating mounting part and the hydrofoil specimen mounted on the rotating mounting part to rotate, thereby adjusting the angle of the hydrofoil specimen.

[0026] As can be seen, during the experiment, the external threaded cylinder 35 and the protective cover 20 together form a seal between the inner limiting ring seat 204 and the rotating disk 19, reducing the agitation of each component with the deionized water in the transparent water tank 7, and making the driving of the hydrofoil specimen smoother and more stable.

[0027] After the experiment, such as Figure 14 As shown, rotating the cover 20 counterclockwise causes the external threaded cylinder 35 to gradually rotate out of the annular groove 27. The cover 20 separates from the rotating disc 19, leaving room for operation. Loosening the locking nut 22 allows for quick disassembly of the hydrofoil specimen, facilitating specimen replacement, maintenance, and internal cleaning of the device, thus improving the overall ease of use of the device.

[0028] The high-speed camera 11 is fixed to the upper right side of the base 1 by a mounting bracket 8, and the top of the mounting bracket 8 is fixed to the fill light 13 by a horizontal frame 12. The computer 10 is mounted on the upper part of the base 1 by a stand 9.

[0029] A sleeve 33 is provided at the middle of the left end of the rotating disk 19. The sleeve 33 is sleeved on the right end of the rotating shaft 5 by a long bolt 23. The right end of the rotating shaft 5 is provided with a bolt hole 21 for the long bolt 23 to extend through. The right end of the rotating disk 19 is provided with circular inner grooves 28 at equal intervals. The rotating mounting part includes a circular fixed seat 29 provided in the circular inner groove 28, a connecting shaft 31 fixed in the middle of the circular fixed seat 29, and a driven gear 32 fixed after the connecting shaft 31 extends through the rotating disk 19. A square through groove 30 is provided between the middle of the circular fixed seat 29, the connecting shaft 31 and the driven gear 32. A bearing 34 is also sleeved on the outside of the connecting shaft 31. The driven gear 32 meshes with the gear ring 24.

[0030] The hydrofoil test piece includes a hydrofoil body 17, a circular mounting plate 18 fixed at the base of the hydrofoil body 17, and a screw 26 fixed in the middle of the circular mounting plate 18 by a square post 25; the square post 25 extends through a square through slot 30, and a locking nut 22 is screwed onto the screw 26.

[0031] The sliding connector includes fixed cylinders 36 evenly spaced on the left end of the cover 20, a sliding rod 38 centrally located inside the fixed cylinder 36, and a spring 37 sleeved on the outside of the sliding rod 38 inside the fixed cylinder 36; positioning cylinders 39 evenly spaced on the left end of the gear ring 24, a sliding hole in the middle between the positioning cylinder 39 and the gear ring 24, the sliding rod 38 being inserted into the sliding hole, the positioning cylinder 39 extending into the spring 37, and the right end of the spring 37 being fixed to the left end surface of the gear ring 24. Under the elastic action of the spring 37, the gear ring 24 is kept close to the left end of the rotating disk 19, and the gear ring 24 is always engaged with the driven gear 32.

[0032] The present invention also provides an experimental method for a rotating hydrofoil cavitation experimental device, specifically including the following steps: S1. By rotating the cover 20 clockwise, the external threaded cylinder 35 is further screwed into the annular groove 27. At this time, the sliding connector on the cover 20 will drive the toothed ring 24 to rotate. The toothed ring 24 will then drive the rotating mounting part and the hydrofoil specimen mounted on the rotating mounting part to rotate, thereby adjusting the angle of the hydrofoil specimen. S2. Computer 10 controls the operation of variable frequency motor 4, so that the rotating shaft 5 drives the hydrofoil specimen to rotate through rotating disk 19. Then, computer 10 controls high-speed camera 11 to continuously collect images and capture the dynamic evolution process of cavitation of hydrofoil specimen under rotating conditions from initiation, development, separation, detachment to collapse in real time. S3. The high-definition image data captured by the high-speed camera 11 is transmitted to the computer 10 in real time for lossless storage. S4. Rotate the cover 20 counterclockwise. After the cover 20 leaves the rotating disk 19, space is created. Then, the hydrofoil test piece can be removed.

[0033] Specifically, when using it: Perform a comprehensive verification of the device: Check if the speed control function of the variable frequency motor 4, the acquisition function of the high-speed camera 11, and the illumination function of the supplementary light 13 are normal. Test the sealing performance of inlet valve 15 and outlet valve 16, as well as the sealing performance of sealing assembly 2, to ensure there is no leakage; Verify the monitoring accuracy of the thermometer and pressure gauge on the transparent water tank 7, ensuring the error is controlled within ±0.5%; check whether the electrical wiring connections are up to standard and eliminate potential safety hazards.

[0034] Pre-experiment assembly stage: The hydrofoil specimen is assembled and fixed as a whole. The hydrofoil specimen consists of hydrofoil body 17, circular mounting plate 18, square column 25 and screw 26. The square column 25 passes through the square through groove 30 inside the rotating mounting part, and then the screw 26 and locking nut 22 are used to lock and fix it, thus completing the quick disassembly and assembly and stable installation of the hydrofoil specimen. The rotating mounting component is assembled inside the circular inner groove 28 at the right end of the rotating disk 19. It consists of a circular fixed seat 29, a connecting shaft 31, a driven gear 32, and a bearing 34. The bearing 34 reduces the rotational friction of the connecting shaft 31, ensuring smooth operation during the angle adjustment process.

[0035] The angle of attack of the hydrofoil specimen can be precisely adjusted mechanically. By rotating the cover 20 clockwise, the sliding connector inside the cover 20 moves synchronously. The sliding connector consists of a fixed cylinder 36, a spring 37, and a sliding rod 38. The sliding rod 38 is inserted into the sliding hole of the positioning cylinder 39 at the left end of the toothed ring 24. Rotating the cover 20 can smoothly drive the toothed ring 24 to rotate synchronously. At the same time, the external threaded cylinder 35 fixed inside the cover 20 is gradually screwed into the annular groove 27 at the left end of the rotating disk 19 to achieve axial limiting and locking. The gear ring 24 meshes with each set of driven gears 32. When the gear ring 24 rotates, it synchronously drives all rotating mounting parts and hydrofoil body 17 to deflect synchronously, thereby uniformly adjusting the installation angle of attack of the hydrofoil specimen to meet the cavitation comparison experiment requirements under different angle of attack conditions.

[0036] Computer 10 electronically controls and adjusts the operating speed of variable frequency motor 4. The output end of variable frequency motor 4 drives the rotating shaft 5 to rotate. The right end of rotating shaft 5 is rigidly fixed to rotating disk 19 through the matching structure of long bolt 23, sleeve 33 and bolt hole 21, thereby driving rotating disk 19 and multiple sets of hydrofoil specimens distributed in the circumferential direction to rotate at a uniform speed inside transparent water tank 7. During the formal experimental phase, the hydrofoil body 17 rotates at high speed in the water in the transparent water tank 7 along with the rotating disk 19. The water flow velocity on the surface of the hydrofoil changes drastically, and a low-pressure environment is generated in a local area. When the local pressure is lower than the saturated vapor pressure of the water, cavitation gradually forms on the surface of the hydrofoil, and then a complete evolution process of cavitation initiation, cavitation development, cavitation separation and shedding and collapse occurs. The fill light 13 provides uniform lighting to eliminate shadows during shooting. The high-speed camera 11 continuously captures high-definition dynamic images, fully recording the cavitation morphology changes throughout the entire cycle. The captured image data is transmitted to the computer 10 in real time for storage, processing, and subsequent analysis.

[0037] After the temperature of the flow field inside the transparent water tank 7 naturally drops to room temperature (25℃) and the pressure returns to normal pressure, slowly open the outlet valve 16 to completely drain the deionized water in the transparent water tank 7.

[0038] After the experiment, rotate the cover 20 counterclockwise to make the external threaded cylinder 35 unscrew the annular groove 27. The cover 20 separates from the rotating disk 19 and leaves room for operation. Loosen the locking nut 22 to quickly disassemble the hydrofoil specimen, which facilitates specimen replacement, maintenance and internal cleaning of the device, and improves the overall ease of use of the device.

[0039] Clean the surface of the hydrofoil specimen, the rotating disk 19, and the internal flow channels of the transparent water tank 7 with clean water to remove any experimental residues; clean the surface of the transparent water tank 7; reset all components, turn off the main power supply, and store the device in a dry, well-ventilated laboratory.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A rotating hydrofoil cavitation experimental device, comprising a base, characterized in that: The upper left side of the base is equipped with a fixed bracket to mount a transparent water tank and a computer-controlled variable frequency motor, while the upper right side of the base is equipped with a high-speed camera connected to the computer signal and a fill light. The rotating shaft at the output end of the variable frequency motor extends into the transparent water tank and is fixed with a rotating disc, and a sealing component is provided at the connection between the rotating shaft and the transparent water tank. Rotary mounting components are provided at equal intervals on the rotating disk. The rotating mounting components are used to install hydrofoil test specimens. An external threaded cylinder is screwed into the annular groove in the middle of the left end of the rotating disk. The left end of the external threaded cylinder is sleeved on the outside of the right end of the sealing assembly. The toothed ring sleeved on the external threaded cylinder meshes with the left end of the rotating mounting component. A protective cover is fixed to the outside of the external threaded cylinder. The protective cover is sleeved on the outside of the left end of the rotating disk. Several sets of sliding connectors are equally spaced on the protective cover and are slidably connected to the left end of the toothed ring. The sealing assembly includes a sleeve fitted onto the rotating shaft via the inside of the transparent water tank, an inner limiting ring seat fixed at the end of the sleeve, and an outer limiting ring seat fitted onto the sleeve after it extends out of the transparent water tank. The inner limiting ring seat has an inner bearing that is sleeved on the rotating shaft embedded inside, and the outer limiting ring seat has an outer bearing that is sleeved on the rotating shaft embedded inside. An inner sealing ring is embedded at one end of the inner limiting ring seat near the sleeve, and a sealing gasket is sleeved on the outer side of the other end of the inner limiting ring seat. The external threaded sleeve is sleeved on the outer side of the inner limiting ring seat. An outer sealing ring is embedded in the inner wall of the outer limiting ring seat; The screw on the outer limiting ring seat passes through the side wall of the transparent water tank and is screwed and fixed to the inner limiting ring seat; The sliding connector includes a fixed cylinder evenly spaced at the left end of the cover, a sliding rod centrally located inside the fixed cylinder, and a spring sleeved on the outside of the sliding rod inside the fixed cylinder. The toothed ring is provided with positioning cylinders at equal intervals on its left end, and a sliding joint hole is provided in the middle between the positioning cylinder and the toothed ring, and the sliding joint rod is inserted into the sliding joint hole; The positioning cylinder extends into the spring, and the right end of the spring is fixed to the left end surface of the toothed ring.

2. The rotating hydrofoil cavitation experimental device according to claim 1, characterized in that: The transparent water tank is equipped with an end cap on the top, and an inlet valve is connected to the inlet pipe on the top of the end cap. An outlet valve is connected to the outlet pipe on the bottom right side of the transparent water tank.

3. The rotating hydrofoil cavitation experimental device according to claim 1, characterized in that: The high-speed camera is fixed to the upper right side of the base using a mounting bracket, and the top of the mounting bracket is fixed to the fill light using a horizontal frame. The computer is mounted on the upper part of the base using a stand.

4. The rotating hydrofoil cavitation experimental device according to claim 1, characterized in that: The rotating disk has a sleeve in the middle of the left end. The sleeve is fixed to the right end of the rotating shaft with a long bolt. The right end of the rotating shaft has a bolt hole for the long bolt to pass through and protrude.

5. The rotating hydrofoil cavitation experimental device according to claim 1, characterized in that: The rotating disk has equally spaced circular inner grooves on its right end; The rotating mounting component includes a circular fixed seat disposed in a circular inner groove, a connecting shaft fixed in the middle of the circular fixed seat, and a driven gear fixed after the connecting shaft extends through and out of the rotating disk. A square through groove is provided between the middle of the circular fixed seat, the connecting shaft, and the driven gear. The driven gear meshes with the ring gear.

6. The rotating hydrofoil cavitation experimental device according to claim 5, characterized in that: The hydrofoil test piece includes a hydrofoil body, a circular mounting plate fixed at the root of the hydrofoil body, and a screw rod fixed in the middle of the circular mounting plate by a square column. The square column extends through a square through slot, and a locking nut is screwed onto the screw.

7. The rotating hydrofoil cavitation experimental device according to claim 1, characterized in that: The transparent water tank is equipped with a heating plate at the bottom, and a thermometer and a pressure gauge are also installed on the transparent water tank. The heating plate, thermometer, and pressure gauge are electrically connected to a computer.

8. An experimental method for the rotating hydrofoil cavitation experimental apparatus according to any one of claims 1-7, characterized in that: Specifically, the following steps are included: S1. By rotating the cover clockwise, the external threaded cylinder is further screwed into the annular groove. At this time, the sliding connector on the cover will drive the toothed ring to rotate, and the toothed ring will drive the rotating mounting part and the hydrofoil specimen installed on the rotating mounting part to rotate, thereby adjusting the angle of the hydrofoil specimen. S2. The computer controls the operation of the variable frequency motor, which drives the hydrofoil specimen to rotate through the rotating disk. Then, the computer controls the high-speed camera to continuously collect images and capture the dynamic evolution process of cavitation of the hydrofoil specimen under rotating conditions from initiation, development, separation, detachment to collapse in real time. S3: High-definition image data captured by the high-speed camera is transmitted to the computer in real time for lossless storage. S4. Rotate the cover counterclockwise until it leaves space behind the rotating disc, then remove the hydrofoil specimen.

Images