An aircraft heat exchanger performance testing apparatus and method

Abstract

The present application relates to the technical field of heat exchanger performance test, and discloses a kind of aircraft heat exchanger performance test equipment, by setting pressure drop detection device and visual acquisition device in water pressure test system, can be judged whether leakage according to leakage rate and visual information identification result, improve test quality and accuracy.And cover and first limit switch are arranged in the water tank of water pressure test, protective cage and second limit switch are arranged on the test table of compression test, if heat exchanger accidental explosion or debris splashing etc., can be separated by cover and protective cage, can prevent heat exchanger from hurting in test.The water tank is also provided with a foot switch, which can conveniently and efficiently guide the test wastewater out.The anti-skid pad on the test table can isolate mechanical vibration and interference, improve test accuracy, and can avoid equipment falling damage or pulling off the connection with the test pipeline, improve safety.The present application also provides a kind of aircraft heat exchanger performance test method using the above-mentioned equipment.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger performance testing technology, and in particular to an aircraft heat exchanger performance testing device and method. Background Technology

[0002] Currently, aircraft heat exchangers require performance testing after cleaning or repair to ensure they meet operational requirements. Performance testing of aircraft heat exchangers includes pressure drop testing and pressure / leakage testing. In pressure drop testing, the heat exchanger is fixed in the testing station, and the inlet and outlet of the heat exchanger's cold and hot ends are connected to test pipelines. Air is supplied to the heat exchanger through the test pipelines, and the pressure at the inlet and outlet of the heat exchanger is measured to determine if there is a pressure drop, thereby determining whether the flow channels are unobstructed, blocked, or have internal short circuits. Pressure / leakage testing involves placing the heat exchanger in a water tank, immersing it in liquid, and pressurizing and holding the pressure in both the tube-side and shell-side chambers to detect any deformation or leakage.

[0003] Existing pressure / leakage tests rely on visual inspection to check for deformation or bubbles on the heat exchanger surface. However, manual observation is subjective, inefficient, prone to misjudging minor or intermittent leaks, and cannot provide accurate leakage rate data or leak location. Furthermore, existing leak tests may use flow meters installed in the heat exchanger to detect pressure drop, but flow meters can only determine the presence and rate of leakage, not the specific location. Moreover, flow meter readings are susceptible to interference from internal leaks in the test pipeline valves and pressure fluctuations caused by temperature changes, leading to false alarms. Additionally, they cannot distinguish between equipment leaks and system errors, resulting in low accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a highly efficient, comprehensive, and accurate testing device and method for aircraft heat exchanger performance.

[0005] To achieve the above objectives, the present invention provides an aircraft heat exchanger performance testing device, including a water pressure testing system. The water pressure testing system includes a water tank, a lifting device, a water pressure pipeline device, a pressure drop detection device, and a visual acquisition device. The lifting device is installed on the water tank and is used to move the heat exchanger up and down in the water tank. The water pressure pipeline device is used to connect to the heat exchanger and introduce gas into the heat exchanger. The pressure drop detection device is used to detect the pressure and temperature of the heat exchanger. The visual acquisition device is located in the water tank and is used to collect visual information about the heat exchanger when it is located in the water tank.

[0006] As a preferred embodiment, the visual acquisition device includes a first visual module and a second visual module. The first visual module is used to acquire three-dimensional shape information of the heat exchanger when it is located in the water tank, and the second visual module is used to acquire video data of the heat exchanger when it is located in the water tank.

[0007] As a preferred embodiment, the water tank includes a tank body and a cover plate, the tank body having a tank opening, and the cover plate being openable and closable at the tank opening.

[0008] As a preferred embodiment, a first limit switch is provided at the opening of the box, and the water pressure pipeline device includes a water pressure test air source. The first limit switch is connected in series in the control circuit of the water pressure test air source. When the cover plate leaves the closed position, the first limit switch is opened, causing the control circuit of the water pressure test air source to be disconnected, thereby cutting off the water pressure pipeline device.

[0009] As a preferred embodiment, the water tank also includes a foot switch, the bottom of the tank is provided with a drain outlet, a drain valve is provided at the drain outlet, the foot switch is installed on the tank, the foot switch is connected to the drain valve through a transmission mechanism, and the foot switch drives the drain valve to open or close the drain outlet by moving up and down.

[0010] As a preferred embodiment, the system further includes a pressure drop testing system, which comprises a test bench, a pressure drop pipeline device, a clamping device, and a protective cage. The pressure drop pipeline device is used to connect to the heat exchanger and introduce gas into the heat exchanger. The clamping device is located on the test bench and is used to limit and fix the heat exchanger. The protective cage is closable and connected to the test bench, and when closed, the protective cage covers the heat exchanger and the clamping device.

[0011] As a preferred embodiment, the pressure drop test system further includes a second limit switch, which is disposed on the test bench. The pressure drop pipeline device includes a pressure drop test gas source, and the second limit switch is connected in series in the control circuit of the pressure drop test gas source. When the protective cage leaves the closed position, the second limit switch is opened, causing the control circuit of the pressure drop test gas source to be disconnected, thereby cutting off the pressure drop pipeline device.

[0012] As a preferred embodiment, the test bench surface is covered with an anti-slip mat. The present invention also provides a method for testing the performance of an aircraft heat exchanger, based on the above-mentioned aircraft heat exchanger performance testing equipment, comprising: The heat exchanger is immersed in a water tank, placing the heat exchanger in a liquid environment; Acquire visual information about a heat exchanger placed in a liquid environment before pressurization; Pressurize the heat exchanger placed in a liquid environment to the test pressure and maintain the pressure. During the pressure holding process, visual information of the heat exchanger placed in the liquid environment is collected in real time, as well as the pressure and temperature of the heat exchanger placed in the liquid environment are collected in real time. The real-time leakage rate is calculated based on the pressure and temperature of the heat exchanger placed in the liquid environment in real time. Based on real-time acquisition of visual information from a heat exchanger placed in a liquid environment, bubble identification is performed to obtain bubble identification results. If the real-time leakage rate exceeds a preset threshold and the bubble identification result shows a continuous flow of bubbles, then the heat exchanger is leaking; if the real-time leakage rate exceeds the preset threshold but the bubble identification result does not identify any bubbles, then a check of the test circuit is prompted; if the real-time leakage rate does not exceed the preset threshold but the bubble identification result shows a continuous flow of bubbles, then the pressure holding time is extended or the test is repeated; if the real-time leakage rate does not exceed the preset threshold and the bubble identification result does not identify any bubbles, then the heat exchanger is not leaking and the leakage test passes. Acquire visual information about a heat exchanger placed in a liquid environment after pressure holding; The visual information of the heat exchanger placed in the liquid environment before pressurization is compared with the visual information of the heat exchanger placed in the liquid environment after pressure holding. If the morphology of the heat exchanger changes, the heat exchanger is deformed during the pressure test.

[0013] As a preferred embodiment, the visual information obtained from the visual information of the heat exchanger placed in the liquid environment before and after pressurization is three-dimensional point cloud data. During the pressure holding process, the visual information from the heat exchanger placed in the liquid environment is collected in real time and is presented as video data.

[0014] Compared with the prior art, the advantages of the present invention are as follows: This invention incorporates a pressure drop detection device and a visual acquisition device into a water pressure testing system. The leakage rate can be obtained from the pressure and temperature detected by the pressure drop detection device, while the visual acquisition device collects visual information from the heat exchanger during pressure / leakage testing. By recognizing this visual information, it can determine whether bubbles are escaping from the heat exchanger. Based on the leakage rate and visual information recognition results, leakage is determined. This eliminates the need for manual observation, resulting in high efficiency, avoiding missed or false detections, and preventing false alarms from the pressure drop detection device, thus improving test quality and accuracy. Furthermore, the visual acquisition device can compare the morphology of the heat exchanger during pressurization and pressure holding to determine deformation. In leakage testing, it can also trace and locate the location of leaks, providing comprehensive detection. Additionally, this invention includes a cover and a first limit switch in the water tank, and a protective cage and a second limit switch on the test platform. In the event of an accidental explosion or debris splashing from the heat exchanger, the cover and protective cage can isolate the area, preventing injury during testing. The water tank also includes a foot switch, which allows for the drainage of test wastewater, making it convenient and efficient. The anti-slip pads on the test bench can isolate mechanical vibration and interference, improve test accuracy, and increase the friction between the heat exchanger and the test bench, preventing equipment from falling and being damaged or breaking the connection with the test pipeline, thus improving safety. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of an aircraft heat exchanger performance testing device according to an embodiment of the present invention.

[0016] Figure 2 This is a top view of the suspended basket according to an embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of the rotating mechanism according to an embodiment of the present invention.

[0018] Figure 4 This is a schematic diagram of the connection between the foot switch and the drain valve in an embodiment of the present invention.

[0019] Figure 5 This is a schematic diagram of the compression testing system according to an embodiment of the present invention.

[0020] Figure 6 This is a schematic diagram of a pressure drop pipeline device according to an embodiment of the present invention.

[0021] Figure 7 This is a flowchart of an aircraft heat exchanger performance testing method according to an embodiment of the present invention.

[0022] In the diagram, 1-water tank; 101-tank body; 102-cover plate; 2-suspended basket; 3-guide rail; 4-hoisting hoist; 5-guide pulley; 6-centering electric push rod; 7-transverse roller group; 8-longitudinal roller group; 9-first vision module; 10-second vision module; 11-rotary motor; 12-drive gear; 13-driven gear ring; 14-mounting base; 15-connecting rod; 16-receiver motor; 17-pitch motor; 18-foot switch; 19-drain valve; 1901-valve stem; 20-first connecting rod; 21-second connecting rod; 22-pin; 23-reset spring; 24-test table; 2401-table surface; 2402-height adjustment 25-Protective cage; 26-Anti-slip mat; 27-Positioning block; 28-Side clamping cylinder; 29-Limiting beam; 30-Telescopic device; 31-Observation protective glass plate; 32-Blower; 33-Fan; 34-First shut-off valve; 35-Second shut-off valve; 36-Third shut-off valve; 37-Fourth shut-off valve; 38-Flow sensor; 39-First absolute pressure sensor; 40-Second absolute pressure sensor; 41-Pressure test temperature sensor; 42-Wind tunnel; 43-Hot end interface; 44-Cold end interface; 45-First branch pipeline; 46-Second branch pipeline; 47-Main pipeline; 48-Hot end pipeline; 49-Cold end pipeline. Detailed Implementation

[0023] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0024] In the description of this invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] Example 1 like Figures 1 to 6 As shown, a preferred embodiment of the present invention provides an aircraft heat exchanger performance testing device, including a water pressure testing system. The water pressure testing system includes a water tank 1, a lifting device, a water pressure pipeline device, a pressure drop detection device, and a visual acquisition device. The lifting device is installed on the water tank 1 and is used to move the heat exchanger up and down in the water tank 1. The water pressure pipeline device is used to connect to the heat exchanger and introduce gas into the heat exchanger. The pressure drop detection device is used to detect the pressure and temperature of the heat exchanger. The visual acquisition device is located in the water tank 1 and is used to collect visual information when the heat exchanger is located in the water tank 1. This embodiment sets up a pressure drop detection device and a visual acquisition device in the water pressure testing system. The leakage rate can be obtained based on the pressure and temperature detected by the pressure drop detection device. The visual acquisition device can collect visual information of the heat exchanger during pressure testing / leakage testing. By recognizing the visual information, it can be determined whether bubbles are emerging from the heat exchanger. Based on the leakage rate and the visual information recognition results, it can be determined whether there is leakage. No manual observation is required, which is highly efficient, avoids missed detections and false detections, and can prevent false alarms from the pressure drop detection device, thus improving the test quality and accuracy. In addition, the visual acquisition device can also compare the morphology of the heat exchanger during pressurization and pressure holding to determine whether there is deformation. In leakage testing, it can also trace and locate the location of leakage, providing comprehensive detection.

[0028] Specifically, the lifting device in this embodiment includes a basket 2, a guide rail 3, and a hoist 4. The guide rail 3 is installed on the inner wall of the water tank 1 and along the height direction of the water tank 1. The basket 2 is movably mounted on the guide rail 3. The side wall of the water tank 1 has a lifting hole communicating with its interior. The outer wall of the water tank 1 has a guide pulley 5. The hoist 4 is located outside the water tank 1. The chain of the hoist 4 passes around the guide pulley 5 and extends into the water tank 1. The hook end of the hoist 4 is connected to the basket 2. The hoist 4 drives the basket 2 to move up and down along the guide rail 3 to achieve lifting. The guide rail 3 has a guide groove extending along its length. The basket 2 has a sliding buckle. The sliding buckle is embedded in the guide groove and can slide along the guide groove. The connection between the sliding buckle and the guide groove can guide the up and down movement of the basket 2 and prevent the basket 2 from deviating. Before testing, the heat exchanger is placed in the suspended basket 2, and the hoist 4 is activated to lower the basket 2 to a predetermined depth, immersing the heat exchanger in the liquid environment. After testing, the hoist 4 is activated to raise the basket 2. The hoist 4 can be an electric hoist or a manual hoist. In this embodiment, four hoist 4 are arranged in a rectangular array. The hook ends of the hoist 4 are connected to the lifting lugs on the basket 2. In this embodiment, the basket 2 has a cuboid structure, and the four hoist 4 are connected to the four corners of the basket 2. Using four hoist 4 ensures that the basket 2 moves smoothly and maintains its balance, preventing the basket 2 from tipping over.

[0029] In addition, the suspended platform 2 is equipped with a centering device, which includes two sets of centering components. One set of centering components is provided in the length direction and another in the width direction of the suspended platform 2. Each centering component includes two electric centering push rods 6, and the two electric centering push rods 6 in the same centering component are located on opposite side walls of the suspended platform 2. The bottom of the suspended platform 2 is provided with a transverse roller group 7 and two longitudinal roller groups 8. The transverse roller group 7 includes multiple transverse rollers, and the longitudinal roller group 8 includes multiple longitudinal rollers. The transverse rollers are arranged along the length direction of the suspended platform 2, and the longitudinal rollers are arranged along the width direction of the suspended platform 2. The four sets of longitudinal roller groups 8 are located on both sides of the transverse roller group 7, so that the transverse roller group 7 is located at the center position of the two longitudinal roller groups 8. When the heat exchanger is placed in the suspended basket 2, it sits on the transverse roller group 7 and the longitudinal roller group 8. The heat exchanger can be moved by extending and retracting an electric push rod. When the heat exchanger moves laterally, the transverse rollers rotate; when it moves longitudinally, the longitudinal rollers rotate. The transverse and longitudinal rollers reduce the resistance to the heat exchanger's movement and prevent damage. Furthermore, the suspended basket 2 in this embodiment is a frame structure composed of multiple basket rods. The basket rods, transverse rollers, and longitudinal rollers are all covered with cushioning pads to prevent impacts and protect the heat exchanger. The suspended basket 2 in this embodiment is made of 304 stainless steel.

[0030] In this embodiment, the visual acquisition device includes a first visual module 9 and a second visual module 10. The first visual module 9 is used to acquire the three-dimensional morphological information of the heat exchanger when it is located in the water tank 1, and the second visual module 10 is used to acquire video data of the heat exchanger when it is located in the water tank 1. The first visual module 9 can acquire the three-dimensional morphology of the heat exchanger immersed in the liquid environment before pressurization and during pressure holding. By comparing the three-dimensional morphology before pressurization and during pressure holding, it can determine whether there are deformations such as bulges, dents, and warping, and obtain the results of the pressure test. The second visual module 10 acquires video of the heat exchanger immersed in the liquid environment during pressure holding. Based on the video, multiple frames of continuous time-series images can be obtained. By identifying the images, it can be determined whether bubbles are generated. Furthermore, by identifying the continuous time-series image frames, it can be determined whether a continuous bubble flow is generated, thereby determining whether the heat exchanger is leaking and obtaining the results of the leakage test.

[0031] Optionally, the first vision module 9 employs a 3D scanner to acquire point cloud data of the heat exchanger. The 3D scanner projects a light pattern onto the surface of the heat exchanger, acquiring the three-dimensional coordinates of each point on the surface of the heat exchanger, generating dense point cloud data. By comparing the point cloud data obtained from two scans, the three-dimensional distance deviation of corresponding points can be obtained, thereby determining whether deformation has occurred. In this embodiment, after the heat exchanger is immersed in a liquid environment, before pressurization, the heat exchanger is scanned to generate reference point cloud data. Subsequently, gas is introduced into the heat exchanger for pressurization. After pressurization, a pressure holding stage is entered. In the early stage of the pressure holding stage, the heat exchanger is scanned again to generate test point cloud data. The reference point cloud data and the test point cloud data are registered, and the three-dimensional distance deviation of corresponding points in the reference point cloud data and the test point cloud data is calculated. If the three-dimensional distance deviation exceeds a preset deformation threshold, deformation occurs. The second vision module 10 uses a 2D camera. The 2D camera is used to continuously capture video of the heat exchanger immersed in the liquid environment of the water tank 1. After a period of pressure holding, when the real-time leakage rate calculated based on the pressure and temperature of the heat exchanger collected by the pressure drop detection device exceeds the preset threshold, image recognition is performed on the video frames before and after the current acquisition time to determine whether there is a continuous bubble flow. If so, leakage occurs.

[0032] Furthermore, the water tank 1 in this embodiment includes a tank body 101 and a cover plate 102. The tank body 101 has a tank opening, and the cover plate 102 is closable at the tank opening. The cover plate 102 is provided to prevent debris from splashing during a pressure test. In addition, the first vision module 9 in this embodiment is connected to the cover plate 102 via a rotating mechanism. The rotating mechanism includes a rotary motor 11, a drive gear 12, a driven gear ring 13, a mounting base 14, a connecting rod 15, a retractor / discharge motor 16, and a pitch motor 17. The rotary motor 11 is mounted on the cover plate 102, the drive gear 12 is sleeved on the output shaft of the rotary motor 11, and the driven gear ring 13 is rotatably mounted on the cover plate 102. The driven gear ring 13 meshes with the drive gear 12. When the rotary motor 11 drives the drive gear 12 to rotate, the drive gear 12 drives the driven gear ring 13 to rotate through meshing. Mounting base 14 is connected to driven gear ring 13. Receiving and discharging motor 16 is mounted on mounting base 14. One end of connecting rod 15 is perpendicularly connected to the output shaft of receiving and discharging motor 16, so that receiving and discharging motor 16 drives connecting rod 15 to rotate and move closer to or away from cover plate 102. Pitch motor 17 is connected to the other end of connecting rod 15. First vision module 9 is connected to the output shaft of pitch motor 17, so that pitch motor 17 drives first vision module 9 to rotate around the vertical direction of connecting rod 15. Connecting rod 15 is an electric telescopic rod. In use, after the heat exchanger is placed on the basket 2 and immersed in the liquid environment, the retractor 16 drives the connecting rod 15 to rotate away from the cover plate 102 until the connecting rod 15 is immersed in the liquid environment. Then, the rotary motor 11 drives the drive gear 12 to rotate, which in turn drives the driven gear ring 13 to rotate. Therefore, the first vision module 9 can be driven to scan around the heat exchanger. By driving the first vision module 9 to rotate through the pitch motor 17 and extending and retracting the connecting rod 15, the top and bottom surfaces of the heat exchanger can be scanned, thereby obtaining complete point cloud data of the heat exchanger surface. In this embodiment, the rotation mechanism is embedded in the cover plate 102, which can prevent the cover plate 102 from hitting the housing 101 and damaging the rotation mechanism when sliding. In addition, in this embodiment, the second vision module 10 is installed on the side wall of the housing 101.

[0033] Specifically, in this embodiment, the cover plate 102 is slidably connected to the housing 101 along its length, and the cover plate 102 opens and closes by sliding. Slide rails are provided on both sides of the top of the housing 101, and sliding wheels are installed at the bottom of the cover plate 102. The sliding wheels are slidably connected to the slide rails, and the cover plate 102 opens and closes by pushing it. Furthermore, the cover plate 102 in this embodiment includes, from top to bottom, an acrylic sheet, a stainless steel mesh, and a mounting plate. The acrylic sheet, stainless steel mesh, and mounting plate are fixed together with bolts. The use of acrylic sheet and stainless steel mesh increases the strength of the cover plate 102 and prevents flying debris from breaking it. A rotating mechanism is mounted on the mounting plate. The stainless steel mesh is woven from 1.2mm diameter stainless steel wire, and the mesh size is 12×12mm. In addition, this embodiment also installs lighting equipment on the side walls and / or side walls of the housing 101 for underwater illumination, facilitating clear visual information acquisition and personnel observation.

[0034] In some embodiments, a first limit switch is provided at the opening of the enclosure. The water pressure pipeline device includes a water pressure testing air source. The first limit switch is connected in series in the control circuit of the water pressure testing air source. When the cover plate 102 leaves the closed position, the first limit switch opens, causing the control circuit of the water pressure testing air source to be disconnected, thereby cutting off the water pressure pipeline device. The first limit switch is a limit switch located at the opening of the enclosure. When the cover plate 102 is closed to the correct position, the cover plate 102 touches the first limit switch, causing the first limit switch to conduct. When the cover plate 102 is not properly closed, the first limit switch does not conduct, and the control circuit of the water pressure testing air source is disconnected, ensuring the safety of the operator and the equipment. Optionally, a first mounting hole is provided at the box opening, a first limit switch is provided in the first mounting hole, and a first lever is provided on the cover plate 102. The first lever is used to insert into the first mounting hole. When the cover plate 102 is correctly closed and closed in place, the first lever extends into the first mounting hole until it touches the first limit switch, thereby triggering the first limit switch and making the first limit switch conduct.

[0035] In addition, a spring positioning pin is provided at the opening of the box. The spring positioning pin is set along the height direction of the box body 101, and a positioning hole is provided on the cover plate 102. The spring positioning pin is located below the cover plate 102. When the cover plate 102 moves into place, the spring positioning pin extends into the positioning hole to perform positioning. The spring positioning pin can prevent the cover plate 102 from sliding during the test.

[0036] The hydraulic pressure piping system also includes a hydraulic pressure test pipeline, through which a hydraulic pressure test gas source is connected to the tube-side or shell-side inlet of the heat exchanger. The pressure drop detection device includes a pressure drop detection pressure sensor and a pressure drop detection temperature sensor; both the tube-side and shell-side chambers of the heat exchanger are equipped with these sensors. During tube-side testing, the hydraulic pressure test pipeline is connected to the tube-side inlet, the tube-side outlet is sealed with a plug, and the tube-side is pressurized using the hydraulic pressure test gas source, followed by pressure holding. During shell-side testing, the hydraulic pressure test pipeline is connected to the shell-side inlet, the shell-side outlet is sealed with a plug, and the shell-side is pressurized using the hydraulic pressure test gas source, followed by pressure holding. The hydraulic pressure piping system also includes a first filter connected to the hydraulic pressure test pipeline. This first filter filters the gas medium entering the heat exchanger; in this embodiment, a 5-micron filter is used. The hydrostatic testing pipeline is equipped with quick-connect couplings for rapid connection or disconnection to or from the tube-side or shell-side inlet of the heat exchanger. Additionally, the cover plate 102 or the side wall of the housing 101 has a pipe inlet communicating with the interior of the housing 101. The hydrostatic testing pipeline extends into the housing 101 through this inlet to connect to the heat exchanger placed on the basket 2. The hydrostatic testing pipeline uses a flexible metal hose, providing excellent extensibility and bending resistance to adapt to complex spatial layouts. In this embodiment, the hydrostatic testing gas source utilizes both workshop pipeline gas and nitrogen cylinders for simultaneous pressurization, suitable for pressure testing and leakage testing.

[0037] In some embodiments, the water tank 1 further includes a foot switch 18. A drain outlet is located at the bottom of the tank body 101, and a drain valve 19 is located at the drain outlet. The foot switch 18 is mounted on the tank body 101 and is connected to the drain valve 19 via a transmission mechanism. The foot switch 18 moves up and down, causing the drain valve 19 to open or close the drain outlet. The transmission mechanism in this embodiment includes a first connecting rod 20 and a second connecting rod 21. The water tank 1 is connected to a base. The middle part of the foot switch 18 is rotatably connected to the base. The first end of the first connecting rod 20 is rotatably connected to one end of the foot switch 18. A return spring 23 is provided between the other end of the foot switch 18 and the base. The second end of the first connecting rod 20 is rotatably connected to the first end of the second connecting rod 21. The second end of the second connecting rod 21 has an elongated hole. A pin 22 is connected to the valve stem 1901 and inserted into the elongated hole, forming a slidable hinged connection between the pin 22 and the second connecting rod 21. When foot switch 18 is pressed, it rotates, compressing the return spring 23. This rotation causes the first connecting rod 20 to move in a planar motion, which in turn causes the second connecting rod 21 to swing, thus causing the valve stem 1901 to move linearly. As the valve stem 1901 moves, the valve plate connected to it moves accordingly, opening the valve to drain water. When foot switch 18 is released, the return spring 23 returns to its original position, causing foot switch 18 to rotate in the opposite direction, moving the valve stem 1901 in the opposite direction and closing the valve. Additionally, drain valve 19 is connected to a drain pipe for discharging or collecting wastewater from water tank 1, maintaining a clean testing environment.

[0038] Example 2 The difference between this embodiment and Embodiment 1 is that, based on Embodiment 1, the aircraft heat exchanger performance testing equipment in this embodiment also includes a pressure drop testing system.

[0039] In this embodiment, the aircraft heat exchanger performance testing equipment also includes a pressure drop testing system. The pressure drop testing system includes a test bench 24, a pressure drop pipeline device, a clamping device, and a protective cage 25. The pressure drop pipeline device is used to connect to the heat exchanger and introduce gas into it. The clamping device is located on the test bench 24 and is used to limit and fix the heat exchanger. The protective cage 25 is closable and connected to the test bench 24, and when closed, it covers the heat exchanger and the clamping device. During testing, the heat exchanger is placed on the platform 2401 of the test bench 24 and fixed in place by the clamping device. The clamping device prevents the heat exchanger from being impacted and shaken by high-pressure gas during the pressure drop test, ensuring test stability. Then, the protective cage 25 is closed, covering the heat exchanger and the clamping device to prevent the heat exchanger on the test bench 24 from flying out and injuring people under the impact of high-pressure gas.

[0040] The test bench 24 in this embodiment includes a table surface 2401 and a height adjustment device 2402. The table surface 2401 is mounted on at least two height adjustment devices 2402. The height adjustment device 2402 drives the table surface 2401 to move up and down to accommodate operators of different heights. The height of the test bench 24 can be lowered before the heat exchanger is placed in front of it, and raised after the heat exchanger is placed in front of it, which facilitates loading and unloading of materials.

[0041] Furthermore, in this embodiment, the test bench 24's surface 2401 is covered with an anti-slip pad 26, which isolates mechanical vibration and interference, improves test accuracy, and increases the friction between the heat exchanger and the surface 2401, preventing equipment from falling and being damaged or breaking the connection with the test pipeline, thus improving safety. The anti-slip pad 26 serves to prevent slipping and damping, while also preventing metal-to-metal contact wear. In addition, the test bench 24 is equipped with a positioning device, which includes multiple positioning blocks 27. The positioning blocks 27 are movably connected to the surface 2401 along its length or width. Specifically, the platform 2401 has a long groove extending along its length or width. The anti-slip pad 26 has a through-hole corresponding to the groove, allowing the bottom end of the positioning block 27 to pass through the hole and slide into the groove. The positioning block 27 has a through-hole with internal threads. A locking bolt is threaded into the locking hole and abuts against the bottom of the groove, thus fixing the positioning block 27. The sliding of the positioning block 27 adapts to the bottom support requirements of heat exchangers of different lengths. Optionally, the bottom of the positioning block 27 and the cross-section of the groove are T-shaped.

[0042] In this embodiment, the clamping device includes a side clamping assembly and a top limiting assembly. The side clamping assembly includes two sets of side clamping cylinders 28, which are symmetrically arranged on both sides of the test bench 24. When the heat exchanger is placed on the positioning block 27, the extended ends of the two sets of side clamping cylinders 28 extend until they abut against the heat exchanger, thereby clamping and fixing the heat exchanger. In this embodiment, the side clamping cylinders 28 are controlled by solenoid valves and can operate synchronously or independently to adapt to the clamping requirements of heat exchangers of different widths. Furthermore, the extended ends of the side clamping cylinders 28 in this embodiment are provided with rubber pressure heads, which can prevent damage to the heat exchanger housing during clamping. The rubber pressure heads have an arc-shaped structure, which can adapt to the angular deviation of the heat exchanger surface, improve the reliability of clamping or clamping, and have a gentler buffering effect, avoiding damage to the heat exchanger from sudden impact forces and extending the service life of the rubber pressure heads. The top limiting assembly includes a limiting beam 29 and two telescopic devices 30. The two telescopic devices 30 are installed near opposite sides of the test bench 24. Both ends of the limiting beam 29 are connected to the top of the telescopic devices 30. The telescopic devices 30 move the limiting beam 29 up and down. Before the heat exchanger is placed on the test bench 24, the telescopic devices 30 raise the limiting beam 29. After the heat exchanger is in place on the test bench 24, the telescopic devices 30 lower the limiting beam 29 until it rests against the top surface of the heat exchanger. This restricts the heat exchanger's vertical movement and can accommodate heat exchangers of different heights. Furthermore, the bottom surface of the limiting beam 29 is equipped with an elastic limiting pad to prevent damage to the heat exchanger.

[0043] Furthermore, the clamping device in this embodiment also includes a controller and a relay. Pressure drop test sensors are provided at the extended end of the side clamping cylinder 28 and on the bottom surface of the limiting beam 29. The pressure drop test sensors are communicatively connected to the controller, and the controller is electrically connected to the relay. The pressure drop pipeline device includes a pressure drop test gas source. The relay is connected in series in the control circuit of the pressure drop test gas source. When the values ​​detected by all pressure drop test sensors reach the threshold, the set clamping force is reached. The PLC sends a signal to the relay, which then conducts, enabling the control circuit of the pressure drop test gas source to conduct. If any pressure drop test sensor detects a value less than the threshold, clamping is not achieved, the control circuit of the pressure drop test gas source is cut off, and the test cannot be performed. This prevents testing when the heat exchanger is not clamped. If gas is introduced into the heat exchanger without clamping, the heat exchanger may move or shake under the impact of high-pressure gas, leading to damage to the heat exchanger or breakage of the pipeline, causing personal injury.

[0044] The pressure drop testing system in this embodiment also includes a second limit switch, which is installed on the test bench 24. The pressure drop pipeline device includes a pressure drop test gas source. The second limit switch is connected in series in the control circuit of the pressure drop test gas source. When the protective cage 25 leaves the closed position, the second limit switch opens, causing the control circuit of the pressure drop test gas source to be disconnected, thereby cutting off the pressure drop pipeline device. The second limit switch is a limit switch, which can be a roller limit switch. The second limit switch is installed on the table surface 2401 of the test bench 24. When the protective cage 25 is closed, the protective cage 25 collides with the second limit switch, causing the second limit switch to conduct, thereby conducting the control circuit of the pressure drop test gas source. This allows the pressure drop test gas source to be controlled to supply test gas to the heat exchanger. However, when the protective cage 25 is not properly closed, the second limit switch does not conduct, the control circuit of the pressure drop test gas source is disconnected, and the pressure drop test gas source cannot supply test gas to the heat exchanger, protecting the operator.

[0045] The test bench 24 has a positioning groove on its surface 2401, which corresponds to the bottom edge of the protective cage 25. When the protective cage 25 is closed on the surface 2401, the bottom side of the protective cage 25 is located in the positioning groove, which limits the movement of the protective cage 25 and prevents it from shifting. Furthermore, this embodiment includes an anti-loosening washer on the bottom side of the protective cage 25. The anti-loosening washer is a rubber ring, which avoids noise when the protective cage 25 is opened and closed, and further prevents displacement of the cage due to high-pressure gas impact. A second mounting hole is provided at the bottom of the positioning groove, and a second limit switch is located in the second mounting hole. A second lever is provided on the bottom surface of the protective cage 25, which is inserted into the second mounting hole. When the protective cage 25 is closed and fully closed, the second lever inserts into the second mounting hole and touches and eventually presses the second limit switch, causing the second limit switch to conduct, thereby enabling the control circuit of the pressure drop test gas source to be connected.

[0046] Specifically, in this embodiment, the protective cage 25 is a rectangular cage with an open bottom. The protective cage 25 includes a top frame and side frames, both of which are mesh structures. The side frames and top frame are connected by an arc-shaped transition section to achieve rounded corners, preventing scratches to operators. One side of the protective cage 25 is rotatably connected to the table surface 2401 of the test bench 24, and the other side of the protective cage 25 is connected to the table surface 2401 of the test bench 24 via a detachable locking buckle. Rotation allows the protective cage 25 to open and close. When the protective cage 25 is placed over the table surface 2401, it is secured by the locking buckle. Furthermore, the locking buckle in this embodiment has a self-locking mechanism, ensuring that it will not loosen due to vibration after being locked, thus ensuring that the second limit switch remains in an effective trigger state. Optionally, The protective cage 25 has an observation window on its side frame, and a protective glass plate 31 is provided at the observation window. The observation window facilitates viewing instrument data during testing, and the protective glass plate 31 can both allow for observation and protect the operator. In this embodiment, the protective cage 25 is made of stainless steel.

[0047] The pressure drop pipeline device also includes a blower 32, a fan 33, a first shut-off valve 34, a second shut-off valve 35, a third shut-off valve 36, a fourth shut-off valve 37, a flow sensor 38, a first absolute pressure sensor 39, a second absolute pressure sensor 40, a pressure test temperature sensor 41, a wind tunnel 42, a hot end interface 43, a cold end interface 44, a first branch pipe 45, a second branch pipe 46, a main pipe 47, a hot end pipe 48, and a cold end pipe 49. One end of the first branch pipe 45 is connected to the blower 32, and the other end is connected to the main pipe 47. The first shut-off valve 34 is located on the first branch pipe 45. One end of the second branch pipe 46 is connected to the fan 33 and the other end is connected to the main pipe 47. The second shut-off valve 35 is installed on the second branch pipe 46. One end of the hot end pipe 48 is connected to the hot end interface 43 and the other end is connected to the main pipe 47. The first absolute pressure sensor 39 and the pressure test temperature sensor 41 are installed on the hot end pipe 48. The cold end interface 44, the wind tunnel 42, and the cold end pipe 49 are connected in sequence. The cold end pipe 49 is connected to the main pipe 47. The fourth shut-off valve 37 is installed on the cold end pipe 49. The second absolute pressure sensor 40 is connected to the cold end interface 44. The flow sensor 38 is installed on the main pipe 47. The heat exchanger is placed on the test bench 24 and positioned using the positioning block 27. The heat exchanger is then pressed down using the clamping device. The hot end interface 43 and the cold end interface 44 are connected to the hot end and cold end connections of the heat exchanger, respectively. The protective cage 25 is closed. After the protective cage 25 is fully closed, the second limit switch is triggered, and the control circuits of the blower 32 and fan 33 are activated. During the hot end test, the first shut-off valve 34 is opened, the second shut-off valve 35 is closed, the blower 32 is started, and the speed of the blower 32 is slowly adjusted until the flow rate reaches 500 m³ / h. Data from the flow sensor 38, the pressure test temperature sensor 41, and the first absolute pressure sensor 39 are collected. The flow rate is determined based on the detection value of the flow sensor 38 to see if the current flow rate meets the requirements. The pressure drop is determined based on the detection values ​​of the pressure test temperature sensor 41 and the first absolute pressure sensor 39 to see if the pressure drop meets the requirements, thus completing the hot end pressure drop test. During the cold-end test, the second shut-off valve 35 is opened, the first shut-off valve 34 is closed, the fan 33 is started, and the fan speed is slowly adjusted to bring the flow rate of the flow meter to 500 m³ / h. Data from the flow sensor 38, the pressure test temperature sensor 41, and the second absolute pressure sensor 40 are collected. The flow rate is determined based on the detection value of the flow sensor 38 to see if the current flow rate meets the requirements. The pressure drop is determined based on the detection values ​​of the pressure test temperature sensor 41 and the second absolute pressure sensor 40 to see if the pressure drop meets the requirements, thus completing the cold-end pressure drop test. The third shut-off valve 36 and the fourth shut-off valve 37 are closed before the test. After connecting the hot-end interface 43 and the cold-end interface 44 to the heat exchanger, the third shut-off valve 36 and the fourth shut-off valve 37 are opened before the test officially begins. The third shut-off valve 36 and the fourth shut-off valve 37 serve a protective function.Blower 32 and the fan serve as the air source for pressure drop testing, forming a high-flow air path suitable for pressure drop testing of heat exchangers.

[0048] The other structures in this embodiment are the same as in Embodiment 1, and will not be described again here.

[0049] Example 3 like Figure 7 As shown, a preferred embodiment of the present invention provides a method for testing the performance of an aircraft heat exchanger, based on the aircraft heat exchanger performance testing equipment described in Embodiment 1 or Embodiment 2, comprising: S1. Immerse the heat exchanger in the water tank 1 to place the heat exchanger in a liquid environment; S2. Obtain visual information of a heat exchanger placed in a liquid environment before pressurization; S3. Pressurize the heat exchanger placed in the liquid environment to the test pressure and maintain the pressure. S4. During the pressure holding process, visual information of the heat exchanger placed in the liquid environment is collected in real time, and the pressure and temperature of the heat exchanger placed in the liquid environment are collected in real time. S5. Calculate the real-time leakage rate based on the pressure and temperature of the heat exchanger placed in the liquid environment in real time; S6. Based on the real-time acquisition of visual information of the heat exchanger placed in the liquid environment, bubble recognition is performed to obtain the bubble recognition result; S7. If the real-time leakage rate exceeds a preset threshold and the bubble identification result detects a continuous flow of bubbles, then the heat exchanger is leaking; if the real-time leakage rate exceeds the preset threshold and the bubble identification result does not detect bubbles, then a prompt to check the test circuit is made; if the real-time leakage rate does not exceed the preset threshold and the bubble identification result detects a continuous flow of bubbles, then the pressure holding time is extended or the test is repeated; if the real-time leakage rate does not exceed the preset threshold and the bubble identification result does not detect bubbles, then the heat exchanger is not leaking and the leakage test is passed. S8. Obtain visual information of a heat exchanger placed in a liquid environment after pressure holding; S9. Compare the visual information of the heat exchanger placed in the liquid environment before pressurization with the visual information of the heat exchanger placed in the liquid environment after pressure holding. If the morphology of the heat exchanger changes, the heat exchanger is deformed during the pressure test.

[0050] This embodiment calculates the pressure drop of the heat exchanger during pressure holding based on the detected pressure and temperature, thus obtaining the real-time leakage rate. When the real-time leakage rate exceeds a threshold, bubble identification is performed based on visual information. The real-time leakage rate in this embodiment is set by the operator based on prior knowledge, and the real-time leakage rate cannot exceed 50%, such as 30%, 40%, or 45%. When the real-time leakage rate exceeds the threshold, it indicates a high probability of leakage. At this time, video data is acquired for a period of time before or after the moment the real-time leakage rate exceeds the threshold. The acquired video data is then analyzed. If a continuous flow of bubbles is found, a leak is confirmed. If no bubbles are found, an abnormality is determined in the water pressure test pipeline, and the pipeline's sealing is checked. This avoids misjudgments caused by internal leakage in the test system's valves. Using a real-time leakage rate exceeding a threshold to trigger visual recognition improves efficiency and enables accurate and targeted identification. Secondly, this embodiment continuously identifies the monitored video data during the pressure holding process. If air bubbles are detected, but the real-time leakage rate does not exceed the threshold, the pressure holding time is extended or the test is repeated to prevent potentially defective equipment from being mistakenly judged as qualified products before leaving the factory. Only when the real-time leakage rate does not exceed the threshold and no air bubbles are detected is it determined that there is no leakage, and the leakage test passes. Using real-time leakage rate and image recognition results to determine whether leakage has occurred improves the accuracy, reliability, and efficiency of the test.

[0051] Specifically, in steps S2 and S8 of this embodiment, the visual information of the heat exchanger placed in the liquid environment before and after pressurization is acquired as 3D point cloud data; in step S4, during the pressure holding process, the visual information of the heat exchanger placed in the liquid environment is acquired in real time as video data. By comparing the 3D point cloud data of the heat exchanger before and after pressurization, it is possible to accurately detect whether the heat exchanger has deformed. During the pressure holding process, the acquired video data can be divided into multiple consecutive video frames for image recognition.

[0052] If the real-time leakage rate exceeds a preset threshold, bubble identification is performed based on visual information for a first preset duration before the real-time leakage rate exceeds the threshold and visual information for a second preset duration after the real-time leakage rate exceeds the threshold, and a bubble identification result is obtained; if the bubble identification result identifies a continuous bubble flow, it is determined that there is leakage in the heat exchanger. In summary, this invention provides an aircraft heat exchanger performance testing device. By incorporating a pressure drop detection device and a visual acquisition device into a hydrostatic testing system, the leakage rate can be obtained based on the pressure and temperature detected by the pressure drop detection device. The visual acquisition device can collect visual information from the heat exchanger during pressure / leakage testing, identifying whether bubbles are escaping from the heat exchanger. Leakage is determined based on the leakage rate and visual information identification results. This eliminates the need for manual observation, resulting in high efficiency, avoiding missed or false detections, and preventing false alarms from the pressure drop detection device, thus improving test quality and accuracy. Furthermore, the visual acquisition device can compare the morphology of the heat exchanger during pressurization and pressure holding to determine deformation, and can also trace and locate the leakage location during leakage testing, providing comprehensive detection. Additionally, this invention includes a cover plate 102 and a first limit switch in the water tank 1, and a protective cage 25 and a second limit switch on the test platform 24. In the event of an accidental explosion or debris splashing from the heat exchanger, the cover plate 102 and the protective cage 25 can isolate the area, preventing injury during testing. The water tank 1 is also equipped with a foot switch 18, which allows the test wastewater to be discharged by stepping on the foot switch 18, making it convenient and efficient to use. The anti-slip pad 26 on the test platform 24 can isolate mechanical vibration and interference, improve test accuracy, and increase the friction between the heat exchanger and the platform 2401, preventing the equipment from falling and being damaged or breaking the connection with the test pipeline, thus improving safety. This embodiment of the invention also provides a method for testing the performance of an aircraft heat exchanger, which uses real-time leakage rate and image recognition results to determine whether leakage has occurred, thereby improving the accuracy, reliability, and efficiency of the test.

[0053] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A performance testing device for aircraft heat exchangers, characterized in that, The system includes a water pressure testing system, comprising a water tank, a lifting device, a water pressure pipeline system, a pressure drop detection device, and a visual acquisition device. The lifting device is mounted on the water tank and is used to move a heat exchanger up and down within the water tank. The water pressure pipeline system is connected to the heat exchanger and introduces gas into it. The pressure drop detection device is used to detect the pressure and temperature of the heat exchanger. The visual acquisition device is located within the water tank and is used to acquire visual information about the heat exchanger when it is positioned within the water tank.

2. The aircraft heat exchanger performance testing equipment according to claim 1, characterized in that, The visual acquisition device includes a first visual module and a second visual module. The first visual module is used to acquire three-dimensional shape information of the heat exchanger when it is located in the water tank, and the second visual module is used to acquire video data of the heat exchanger when it is located in the water tank.

3. The aircraft heat exchanger performance testing equipment according to claim 1, characterized in that, The water tank includes a tank body and a cover plate. The tank body has a tank opening, and the cover plate is closable at the tank opening.

4. The aircraft heat exchanger performance testing equipment according to claim 3, characterized in that, A first limit switch is provided at the opening of the box. The water pressure pipeline device includes a water pressure test air source. The first limit switch is connected in series in the control circuit of the water pressure test air source. When the cover plate leaves the closed position, the first limit switch is opened, causing the control circuit of the water pressure test air source to be disconnected, thereby cutting off the water pressure pipeline device.

5. The aircraft heat exchanger performance testing equipment according to claim 3, characterized in that, The water tank also includes a foot switch. The bottom of the tank is provided with a drain outlet and a drain valve is provided at the drain outlet. The foot switch is installed on the tank and is connected to the drain valve through a transmission mechanism. The foot switch drives the drain valve to open or close the drain outlet by moving up and down.

6. The aircraft heat exchanger performance testing equipment according to claim 1, characterized in that, It also includes a pressure drop testing system, which includes a test bench, a pressure drop pipeline device, a clamping device, and a protective cage. The pressure drop pipeline device is used to connect to the heat exchanger and introduce gas into the heat exchanger. The clamping device is located on the test bench and is used to limit and fix the heat exchanger. The protective cage is closable and connected to the test bench. When closed, the protective cage covers the heat exchanger and the clamping device.

7. The aircraft heat exchanger performance testing equipment according to claim 6, characterized in that, The pressure drop test system also includes a second limit switch, which is installed on the test bench. The pressure drop pipeline device includes a pressure drop test gas source. The second limit switch is connected in series in the control circuit of the pressure drop test gas source. When the protective cage leaves the closed position, the second limit switch opens, causing the control circuit of the pressure drop test gas source to be disconnected, thereby cutting off the pressure drop pipeline device.

8. The aircraft heat exchanger performance testing equipment according to claim 6, characterized in that, The test bench surface is covered with an anti-slip mat.

9. A method for testing the performance of an aircraft heat exchanger, based on the aircraft heat exchanger performance testing equipment according to any one of claims 1-8, characterized in that, include: The heat exchanger is immersed in a water tank, placing the heat exchanger in a liquid environment; Acquire visual information about a heat exchanger placed in a liquid environment before pressurization; Pressurize the heat exchanger placed in a liquid environment to the test pressure and maintain the pressure. During the pressure holding process, visual information of the heat exchanger placed in the liquid environment is collected in real time, as well as the pressure and temperature of the heat exchanger placed in the liquid environment are collected in real time. The real-time leakage rate is calculated based on the pressure and temperature of the heat exchanger placed in the liquid environment in real time. Based on real-time acquisition of visual information from a heat exchanger placed in a liquid environment, bubble identification is performed to obtain bubble identification results. If the real-time leakage rate exceeds a preset threshold and the bubble identification result identifies a continuous flow of bubbles, then the heat exchanger is leaking. If the real-time leakage rate exceeds the preset threshold and the bubble identification result does not identify any bubbles, a prompt will be made to check the test circuit; if the real-time leakage rate does not exceed the preset threshold and the bubble identification result identifies a continuous flow of bubbles, the pressure holding time will be extended or the test will be repeated. If the real-time leakage rate does not exceed the preset threshold and the bubble identification result does not identify any bubbles, then the heat exchanger has no leakage and the leakage test is passed. Acquire visual information about a heat exchanger placed in a liquid environment after pressure holding; The visual information of the heat exchanger placed in the liquid environment before pressurization is compared with the visual information of the heat exchanger placed in the liquid environment after pressure holding. If the morphology of the heat exchanger changes, the heat exchanger is deformed during the pressure test.

10. The method for testing the performance of an aircraft heat exchanger according to claim 9, characterized in that, The visual information obtained from the visual information of the heat exchanger placed in the liquid environment before and after pressurization is three-dimensional point cloud data. During the pressure holding process, the visual information from the heat exchanger placed in the liquid environment is collected in real time and is presented as video data.

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