Flexible material air tightness test system and method coupled with pressure-temperature-damage

Abstract

The application discloses a kind of air pressure-temperature-damage coupling's flexible material air tightness test system and method, test system includes tensile fatigue device, sample holder, high-pressure permeation device, fixed support device and holder, the two ends of sample are fixed by sample holder, first fixed in tensile fatigue device to carry out cyclic tension test with sample holder, to obtain the sample with different fatigue damage degree;Through holder, the sample after cyclic tension is transferred and fixed on fixed support device, so that the center test area of sample is located in the high-pressure sealed box permeation region formed by upper box assembly and lower box assembly in high-pressure permeation device, so as to carry out air tightness detection under different temperature and different air pressure, to obtain the gas permeation rate and gas permeation coefficient of sample, realize the overall evaluation of flexible material air tightness and fatigue resistance.

Description

Technical Field

[0001] This invention belongs to the field of material performance testing technology, and specifically relates to a pressure-temperature-damage coupled air tightness testing system and method for flexible materials. Background Technology

[0002] Compressed air energy storage technology, as a large-scale physical energy storage technology, utilizes electrical energy to drive a compressor during the energy storage process, generating high-pressure air which is then stored in a gas storage tank. During energy release, the air in the storage device expands, driving a turbine generator to produce electricity. Existing compressed air energy storage artificial underground caverns typically consist of surrounding rock, concrete lining, and a sealing layer. The surrounding rock bears the cavern pressure, the lining transmits the pressure, and the sealing layer seals the gas stored in the cavern.

[0003] In recent years, numerous researchers both domestically and internationally have dedicated themselves to exploring the use of flexible polymer materials to replace traditional steel linings as sealing layers. While flexible polymer materials have lower permeability compared to steel plates, this value is still higher. During the operation of underground caverns, due to the coupled effects of pressure, temperature, and fatigue damage, flexible polymer materials still pose a risk of air leakage. Therefore, to ensure the airtightness of underground gas storage caverns and prevent or control air leakage within acceptable limits, evaluating the airtightness and fatigue resistance of the sealing layer materials becomes crucial. However, existing airtightness testing systems for flexible polymer materials do not consider the impact of the coupling effect of pressure-temperature-fatigue damage on the material's airtightness during actual compressed gas storage operation.

[0004] Therefore, how to provide a pressure-temperature-damage coupled flexible material airtightness testing system to simulate the real engineering environment to the greatest extent and to comprehensively evaluate the airtightness and fatigue resistance of the sealing layer material is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a pressure-temperature-damage coupled air tightness testing system and method for flexible materials to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the first aspect of the present invention provides a pressure-temperature-damage coupled air tightness testing system for flexible materials. The testing system includes: a tensile fatigue device comprising a tensile transmission assembly and a steel column, the steel column being fixed to one end of the tensile transmission assembly; a specimen holder comprising a first clamp and a second clamp, the first clamp being detachably connected to the steel column for clamping one end of the specimen; the second clamp being detachably connected to the other end of the tensile transmission assembly for clamping the other end of the specimen; a high-pressure permeation device comprising a high-pressure sealed box composed of an upper box assembly and a lower box assembly, a pre-reserved gap between the upper box assembly and the lower box assembly for accommodating the central region of the specimen, the upper box assembly and the lower box assembly being connected by bolts; and a fixed support device comprising a fixed component, a first support frame, and a second support. The system comprises a frame and a base plate, wherein a fixing component is fixed to the base plate, one end of the fixing component is detachably connected to the first clamp, and the other end of the fixing component is detachably connected to the second clamp; one end of the first support frame is fixedly connected to the base plate, and the other end of the first support frame is connected to one side of the lower box assembly; one end of the second support frame is fixedly connected to the base plate, and the other end of the second support frame is connected to the other side of the lower box assembly; a lifting device includes a horizontal bar, a first vertical bar, and a second vertical bar, one end of the horizontal bar being provided with a sliding groove; one end of the first vertical bar is fixedly connected to the other end of the horizontal bar, and the other end of the first vertical bar is detachably connected to the first clamp; one end of the second vertical bar is slidably connected to the sliding groove, and the other end of the second vertical bar is detachably connected to the second clamp.

[0007] In the first aspect, the tension transmission assembly includes: a platform plate and a motor; a servo cylinder, the servo cylinder being vertically fixed to one end of the platform plate via a cylinder support; the servo cylinder being connected to the motor; a baffle, the baffle being vertically fixed to the other end of the platform plate; a moving block, disposed between the servo cylinder and the baffle, the moving block being detachably connected to the second clamp, the moving block being provided with bearings and pressure sensor seats at intervals; a guide rod, one end of the guide rod being fixedly connected to the steel column, the other end of the guide rod passing through the bearing and being fixedly connected to the baffle; and a push rod, one end of the push rod being fixedly disposed inside the servo cylinder, the other end of the push rod being fixedly connected to the pressure sensor seat.

[0008] In the first aspect, the tensile fatigue device further includes: a tensile electrical control box, which is communicatively connected to the motor and used to control the operating status of the servo cylinder.

[0009] In the first aspect, the high-pressure permeation apparatus further includes: an oil bath connected to the upper chamber assembly for adjusting the temperature inside the upper chamber assembly; a data acquisition unit for acquiring the pressure and temperature inside the upper chamber assembly and the lower chamber assembly; a data processor for processing the pressure and temperature acquired by the data acquisition unit to obtain the gas permeability and gas permeability coefficient of the sample; a permeation control box including a controller, a pressure stabilizing container, a vacuum pump, and a gas source, one end of the pressure stabilizing container being connected to the gas source, and the other end of the pressure stabilizing container being connected to the upper chamber assembly; the vacuum pump being used to remove gas from the upper chamber assembly and the lower chamber assembly; and the controller being communicatively connected to the pressure stabilizing container, the vacuum pump, and the gas source, respectively.

[0010] In the first aspect, the upper box assembly includes: a first porous stainless steel plate, the first porous stainless steel plate having vent holes, and the bottom surface of the first porous stainless steel plate abutting against the upper surface of the sample; an upper pressure chamber, the upper pressure chamber having the first porous stainless steel plate disposed inside; an oil bath pipe, the oil bath pipe being disposed outside the upper pressure chamber and connected to the oil bath tank to adjust the temperature inside the upper pressure chamber; an upper box body, the upper box body being sleeved outside the oil bath pipe, the upper box body and the lower box assembly being connected by bolts; and an upper thermocouple. The probe end of the upper long thermocouple is located on the upper surface of the sample, and the lead end of the upper long thermocouple is connected to the data acquisition device; the probe end of the upper short thermocouple is located inside the upper pressure chamber, and the lead end of the upper short thermocouple is connected to the data acquisition device; a high-pressure inlet pipe is located at one end inside the upper pressure chamber, and the other end of the high-pressure inlet pipe is connected to the pressure stabilizing container; an upper pressure sensor is located on the high-pressure inlet pipe and is used to monitor the pressure inside the upper pressure chamber; the upper pressure sensor is connected to the data acquisition device.

[0011] In the first aspect, the lower box assembly includes: a second porous stainless steel plate with vent holes, the top surface of which abuts against the lower surface of the sample; a lower pressure chamber, the second porous stainless steel plate being disposed inside the lower pressure chamber; a lower box body, the lower box body being sleeved outside the lower pressure chamber, the lower box body and the upper box body being connected by bolts, one side of the lower box body being connected to the other end of the first support frame, and the other side of the lower box body being connected to the other end of the second support frame; a lower short thermocouple, the probe end of which is located inside the lower pressure chamber, and the lead end of which is connected to the data acquisition device; a low-pressure vent pipe, one end of which is located inside the lower pressure chamber, and the other end of which is connected to the vacuum pump; a lower pressure sensor, located on the low-pressure vent pipe, for monitoring the pressure inside the lower pressure chamber; and the lower pressure sensor being connected to the data acquisition device.

[0012] In the first aspect, the fixing assembly includes: a slide rail fixed to the base plate; a first slider, one end of which is detachably connected to the slide rail and the other end of which is detachably connected to the first clamp; a second slider, one end of which is detachably connected to the slide rail and the other end of which is detachably connected to the second clamp; wherein the first support frame and the second support frame are located between the first slider and the second slider.

[0013] The second aspect of this invention provides a pressure-temperature-damage coupled air tightness testing method for flexible materials. The method utilizes the pressure-temperature-damage coupled air tightness testing system described in the first aspect to test the air tightness of the flexible material. The testing method includes: fabricating the flexible material into a dumbbell-shaped specimen; fixing one end of the specimen to a first clamp and the other end to a second clamp; fixing the first clamp to a steel column and the second clamp to a tensile transmission assembly; performing cyclic tensioning tests on the specimen using the tensile transmission assembly to obtain specimens with different degrees of fatigue damage; and adjusting one end of a second vertical rod within a groove on a horizontal rod according to the distance between the first and second clamps. Positioning is such that the distance between the second vertical rod and the first vertical rod is equal to the distance between the first clamp and the second clamp. The first clamp and the second clamp are transferred from the tensile fatigue device to the fixing assembly and fixed using a lifting device. The fixing assembly is fixed to the base plate, and the first support frame and the second support frame are fixed to the base plate, with the first support frame and the second support frame located below the central region of the sample. The upper box assembly and the lower box assembly are connected by bolts, with the central region of the sample located in the gap reserved between the upper box assembly and the lower box assembly, so that the central region of the sample is completely sealed. A high-pressure penetration test is performed on the central region of the sample to detect the airtightness of the sample.

[0014] In the second aspect, the high-pressure permeation test on the central region of the sample includes: heating the temperature of the upper pressure chamber to a preset temperature using an oil bath; controlling a vacuum pump to evacuate both the lower and upper pressure chambers using a controller until the pressure in the lower pressure chamber remains constant after the vacuum pump is turned off; controlling a gas source and a pressure stabilizing container using a controller to deliver filtered gas to the upper pressure chamber until the upper pressure chamber reaches a preset pressure; and acquiring experimental parameters using a data acquisition unit and a data processor to calculate the gas permeability and gas permeability coefficient of the sample.

[0015] In the second aspect, the formula for calculating the gas permeability (GTR) is:

[0016] ;

[0017] in, Let T be the volume of the pressure chamber and T be the temperature of the upper surface of the sample. The pressure of the test gas in the pressure chamber is given by [insert pressure here], and A is the gas permeation area. R represents the pressure change per unit time in the lower pressure chamber, where R is the gas constant.

[0018] The formula for calculating the gas permeability coefficient Q is:

[0019] ;

[0020] Where d is the thickness of the sample.

[0021] Beneficial effects:

[0022] This invention provides a pressure-temperature-damage coupled air tightness testing system for flexible materials, comprising a tensile fatigue device, a specimen holder, a high-pressure permeation device, a fixing support device, and a lifting device. The specimen holder includes a first clamp and a second clamp. The first clamp holds one end of the specimen, and the second clamp holds the other end. The tensile fatigue device includes a tensile transmission assembly and a steel column. One end of the tensile transmission assembly is fixed to the steel column, and the other end is detachably connected to the second clamp. The first clamp is detachably connected to the steel column, allowing the specimen to be fixed to the tensile transmission assembly via the first and second clamps, thereby subjecting the specimen to cyclic tensile fatigue damage. The lifting device includes a horizontal bar, a first vertical bar, and a second vertical bar. A groove is provided at one end of the horizontal bar. One end of the first vertical bar is fixedly connected to the other end of the horizontal bar, and the other end is detachably connected to the first clamp. One end of the second vertical bar is slidably connected to the groove, and the other end is detachably connected to the second clamp. The first and second vertical bars can be adjusted via the groove. The distance between the rods is adjusted to accommodate the distance between the first and second clamps. The fixed support device includes a fixed component, a first support frame, a second support frame, and a base plate. The fixed component, the first support frame, and the second support frame are all fixed to the base plate. One end of the fixed component is detachably connected to the first clamp, and the other end of the fixed component is detachably connected to the second clamp. The sample is transferred from the tensile fatigue device to the fixed component through the detachable connection, so as to perform a high-pressure penetration test on the sample after tensile fatigue damage. The high-pressure penetration device includes a high-pressure sealed box composed of an upper box assembly and a lower box assembly. The upper box assembly and the lower box assembly are connected by bolts, and the gap reserved between the upper box assembly and the lower box assembly can accommodate the central area of ​​the sample, thereby forming the test area for the high-pressure penetration test. Furthermore, by fixing the first support frame to one side of the lower box assembly and the second support frame to the other side of the lower box assembly, space is reserved above and below the high-pressure sealed box to facilitate the installation of the upper box assembly and the lower box assembly. This invention fixes the sample holder at both ends of the sample, transfers the sample holder from the tensile fatigue device to the fixed support device by the lifting device, and assembles the high-pressure permeation device in the central area of ​​the sample, so that the central area of ​​the sample is in a sealed state, thereby realizing the high-pressure permeation test of the sample and obtaining the gas permeability and gas permeability coefficient of the sample. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a pressure-temperature-damage coupled flexible material air tightness testing system according to the present invention;

[0025] Figure 2 This is a schematic diagram of the tensile fatigue device in this invention;

[0026] Figure 3 This is a schematic diagram of the high-pressure sealing box in this invention;

[0027] Figure 4 This is a cross-sectional schematic diagram of the high-pressure sealing box in this invention;

[0028] Figure 5 This is a schematic diagram of the fixed support device in this invention;

[0029] Figure 6 This is a schematic diagram of the dumbbell-shaped tablet sample in this invention;

[0030] Figure 7 This is a schematic diagram of the pipeline control connection of the high-pressure permeation device in this invention;

[0031] Figure 8 This is a schematic diagram of the gas permeation curve of the sample in this invention;

[0032] Figure label:

[0033] 1. Tensile fatigue device; 11. Tensile transmission assembly; 111. Platform plate; 112. Motor; 113. Servo electric cylinder; 114. Baffle; 115. Moving block; 116. Bearing; 117. Pressure sensor seat; 118. Guide rod; 119. Push rod; 120. Electric cylinder support; 12. Steel column;

[0034] 2. Sample holder; 21. First clamp; 22. Second clamp;

[0035] 3. High-pressure permeation device; 31. Upper box assembly; 311. First porous stainless steel plate; 312. Upper pressure chamber; 313. Oil bath pipe; 314. Upper box body; 315. Upper long thermocouple; 316. Upper short thermocouple; 317. High-pressure inlet pipe; 318. Upper pressure sensor; 32. Lower box assembly; 321. Second porous stainless steel plate; 322. Lower pressure chamber; 323. Lower box body; 324. Lower short thermocouple; 325. Low-pressure outlet pipe; 326. Lower pressure sensor; 33. Oil bath tank; 34. Data acquisition unit; 35. Data processor; 36. Permeation control box; 361. Controller; 362. Pressure stabilizing container; 363. Vacuum pump; 364. Gas source; 37. O-ring seal;

[0036] 4. Fixed support device; 41. Fixed component; 411. Slide rail; 412. First slider; 413. Second slider; 42. First support frame; 43. Second support frame; 44. Base plate;

[0037] 5. Lifting device; 51. Horizontal bar; 52. First vertical bar; 53. Second vertical bar; 54. Slide groove;

[0038] 6. Sample;

[0039] 7. Flexible protective sleeve. Detailed Implementation

[0040] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0041] Example 1

[0042] Please see Figure 1-2This invention provides a pressure-temperature-damage coupled air tightness testing system for flexible materials. The testing system includes: a tensile fatigue device 1, comprising a tensile transmission assembly 11 and a steel column 12, the steel column 12 being fixed to one end of the tensile transmission assembly 11; a specimen holder 2, comprising a first clamp 21 and a second clamp 22, the first clamp 21 being detachably connected to the steel column 12 for clamping one end of a specimen 6; the second clamp 22 being detachably connected to the other end of the tensile transmission assembly 11 for clamping the other end of the specimen 6; a high-pressure permeation device 3, comprising a high-pressure sealed box composed of an upper box assembly 31 and a lower box assembly 32, the gap between the upper box assembly 31 and the lower box assembly 32 being used to accommodate the central area of ​​the specimen 6, the upper box assembly 31 and the lower box assembly 32 being connected by bolts; and a fixed support device 4, comprising a fixed assembly 41, a first support frame 42, a second support frame 43, and a base plate 44. Component 41 is fixed to the base plate 44. One end of the fixing component 41 is detachably connected to the first clamp 21, and the other end of the fixing component 41 is detachably connected to the second clamp 22. One end of the first support frame 42 is fixedly connected to the base plate 44, and the other end of the first support frame 42 is connected to one side of the lower box assembly 32. One end of the second support frame 43 is fixedly connected to the base plate 44, and the other end of the second support frame 43 is connected to the other side of the lower box assembly 32. The lifting device 5 includes a horizontal bar 51, a first vertical bar 52, and a second vertical bar 53. One end of the horizontal bar 51 is provided with a sliding groove 54. One end of the first vertical bar 52 is fixedly connected to the other end of the horizontal bar 51, and the other end of the first vertical bar 52 is detachably connected to the first clamp 21. One end of the second vertical bar 53 is slidably connected to the sliding groove 54, and the other end of the second vertical bar 53 is detachably connected to the second clamp 22.

[0043] Specifically, this invention provides a pressure-temperature-damage coupled air tightness testing system for flexible materials, including a tensile fatigue device 1, a specimen holder 2, a high-pressure permeation device 3, a fixing support device 4, and a lifting device 5. The specimen holder 2 includes a first clamp 21 and a second clamp 22. The first clamp 21 clamps one end of the specimen 6, and the second clamp 22 clamps the other end of the specimen 6. The tensile fatigue device 1 includes a tensile transmission assembly 11 and a steel column 12. One end of the tensile transmission assembly 11 is fixed to the steel column 12, and the other end is detachably connected to the second clamp 22. The first clamp 21 and the steel column 12... The detachable connection allows the sample 6 to be fixed to the tensile transmission assembly 11 via the first clamp 21 and the second clamp 22, thereby subjecting the sample 6 to cyclic tensile fatigue damage. The holder 5 includes a horizontal bar 51, a first vertical bar 52, and a second vertical bar 53. A groove 54 is provided at one end of the horizontal bar 51. One end of the first vertical bar 52 is fixedly connected to the other end of the horizontal bar 51, and the other end of the first vertical bar 52 is detachably connected to the first clamp 21. One end of the second vertical bar 53 is slidably connected to the groove 54, and the other end of the second vertical bar 53 is detachably connected to the second clamp 22. The first vertical bar 52 can be adjusted via the groove 54. The distance between rod 52 and the second vertical rod 53 is adjusted to accommodate the distance between the first clamp 21 and the second clamp 22. The fixed support device 4 includes a fixed component 41, a first support frame 42, a second support frame 43, and a base plate 44. The fixed component 41, the first support frame 42, and the second support frame 43 are all fixed to the base plate 44. One end of the fixed component 41 is detachably connected to the first clamp 21, and the other end of the fixed component 41 is detachably connected to the second clamp 22. The sample 6 is transferred from the tensile fatigue device 1 to the fixed component 41 through the detachable connection, so as to facilitate the treatment of tensile fatigue damage. The high-pressure permeation device 3 includes a high-pressure sealed box composed of an upper box assembly 31 and a lower box assembly 32. The upper box assembly 31 and the lower box assembly 32 are connected by bolts, and the gap reserved between the upper box assembly 31 and the lower box assembly 32 can accommodate the central area of ​​the sample, thereby forming the test area for the high-pressure permeation test. Furthermore, by fixing the first support frame 42 to one side of the lower box assembly 32 and the second support frame 43 to the other side of the lower box assembly 32, space is reserved above and below the high-pressure sealed box to facilitate the installation of the upper box assembly 31 and the lower box assembly 32. In this invention, the sample holder 2 is fixed at both ends of the sample 6. The sample holder 2 is transferred from the tensile fatigue device 1 to the fixed support device 4 by the lifting device 5, and the high-pressure permeation device 3 is assembled in the central area of ​​the sample 6, so that the central area of ​​the sample 6 is in a sealed state, thereby realizing the high-pressure permeation test of the sample 6, obtaining the gas permeability and gas permeability coefficient of the sample 6, and then judging the airtightness of the sample 6.

[0044] It should be added that, in order to reduce the temperature loss inside the high-pressure sealing box, a flexible protective sleeve 7 is wrapped around the outside of the high-pressure sealing box. The flexible protective sleeve 7 is removable and is used to wrap and seal the upper box assembly 31 and the lower box assembly 32 after assembly to prevent heat loss and thus maintain the temperature inside the high-pressure sealing box.

[0045] In some possible embodiments, the tension transmission assembly 11 includes: a platform plate 111 and a motor 112; a servo cylinder 113, which is vertically fixed to one end of the platform plate 111 via a cylinder support 120; the servo cylinder 113 is connected to the motor 112; a baffle 114, which is vertically fixed to the other end of the platform plate 111; and a moving block 115, disposed between the servo cylinder 113 and the baffle 114, which is detachably connected to the second clamp 22, and bearings 116 and pressure sensor seats 117 are spaced apart on the moving block 115. Guide rod 118, one end of which is fixedly connected to the steel column 12, and the other end of which passes through the bearing 116 and is fixedly connected to the baffle 114; push rod 119, one end of which is fixedly disposed inside the servo cylinder 113, and the other end of which is fixedly connected to the pressure sensor seat.

[0046] Specifically, the tension transmission assembly 11 includes a platform plate 111, a motor 112, a servo cylinder 113, a baffle 114, a moving block 115, a guide rod 118, and a push rod 119. The servo cylinder 113 is vertically fixed to one end of the platform plate 111 via a cylinder support 120, and is connected to the motor 112 so that the motor 112 drives the servo cylinder 113 to run. The baffle 114 is vertically fixed to the other end of the platform plate 111. The moving block 115 is disposed between the servo cylinder 113 and the baffle 114 and does not contact the platform plate 111. The moving block 115 is detachably connected to the second clamp 22 and moves within the platform plate 111. A bearing 116 and a pressure sensor seat 117 are installed on the moving block 115. One end of the guide rod 118 is fixedly connected to the steel column 12, and the other end of the guide rod 118 passes through the bearing 116 and is fixedly connected to the baffle 114 to guide the moving block 115 to make linear movements and ensure the stability of the sample 6 in the tensile movement. One end of the push rod 119 is fixedly installed inside the servo cylinder 113, and the other end of the push rod 119 is fixedly connected to the pressure sensor seat 117. The push rod 119 is driven to move by the servo cylinder 113, which in turn drives the moving block 115 to move, so as to perform cyclic tension tests on the sample 6 to obtain samples 6 with different fatigue damage degrees.

[0047] Furthermore, to improve efficiency and accuracy, with the servo cylinder 113 as the axis, steel columns 12, guide rods 118, first clamps 21 and second clamps 22 are respectively set on both sides of the servo cylinder 113. Two bearings 116 are set on the moving block 115, so that the tension transmission assembly 11 can simultaneously perform cyclic tension tests on two specimens 6. At the same time, in order to balance the bending moment and make the specimen 6 perform axial tension movement in one direction, the axes of the push rod 119 and the guide rod 118 need to be at the same height, and also at the same height as the axis of the specimen 6.

[0048] In some possible implementations, the tensile fatigue device 1 further includes a tensile electrical control box, which is communicatively connected to the motor 112 and used to control the operating status of the servo cylinder 113.

[0049] In this application, the tensile fatigue device 1 also includes a tensile electrical control box, which is connected to the motor 112. The tensile electrical control box is controlled by a PLC program. The PLC program controls the operating status of the servo cylinder 113, thereby regulating the tensile stroke and frequency of the push rod 119, so that the push rod 119 drives the moving block 115 to perform linear reciprocating motion along the axis, and obtains specimens 6 with different degrees of fatigue damage.

[0050] In some possible implementations, the high-pressure permeation device 3 further includes: an oil bath 33 connected to the upper box assembly 31 for adjusting the temperature inside the upper box assembly 31; a data acquisition unit 34 for acquiring the pressure and temperature inside the upper box assembly 31 and the lower box assembly 32; a data processor 35 for processing the pressure and temperature acquired by the data acquisition unit 34 to obtain the gas permeability and gas permeability coefficient of the sample 6; and a permeation control box 36, including a controller 361, a pressure stabilizing container 362, a vacuum pump 363, and a gas source 364, one end of the pressure stabilizing container 362 being connected to the gas source 364, and the other end of the pressure stabilizing container 362 being connected to the upper box assembly 31; the vacuum pump 363 being used to remove the gas inside the upper box assembly 31 and the lower box assembly 32; and the controller 361 being communicatively connected to the pressure stabilizing container 362, the vacuum pump 363, and the gas source 364.

[0051] For some possible implementations, please refer to Figure 3-4The upper box assembly 31 includes: a first porous stainless steel plate 311, which has ventilation holes and whose bottom surface abuts against the upper surface of the sample 6; an upper pressure chamber 312, in which the first porous stainless steel plate 311 is disposed; an oil bath pipe 313, which is disposed outside the upper pressure chamber 312 and connected to the oil bath box 33 to adjust the temperature inside the upper pressure chamber 312; an upper box body 314, which is sleeved on the outside of the oil bath pipe 313 and is bolted to the lower box assembly 32; and an upper thermocouple 315. The probe end of thermocouple 315 is located on the upper surface of sample 6, and the lead end of the upper long thermocouple 315 is connected to the data acquisition device 34; the probe end of upper short thermocouple 316 is located inside the upper pressure chamber 312, and the lead end of upper short thermocouple 316 is connected to the data acquisition device 34; a high-pressure inlet pipe 317 is located at one end inside the upper pressure chamber 312, and the other end of the high-pressure inlet pipe 317 is connected to the pressure stabilizing container 362; an upper pressure sensor 318 is located on the high-pressure inlet pipe 317 and is used to monitor the pressure inside the upper pressure chamber 312; the upper pressure sensor 318 is connected to the data acquisition device 34.

[0052] In this application, the upper box assembly 31 includes a first porous stainless steel plate 311, an upper pressure chamber 312, an oil bath pipe 313, an upper box body 314, an upper long thermocouple 315, an upper short thermocouple 316, a high-pressure air inlet pipe 317, and an upper pressure sensor 318. The first porous stainless steel plate 311 has vent holes, and its bottom surface abuts against the upper surface of the sample 6, allowing test gas to reach the sample 6 through the vent holes during the high-pressure permeation test. The upper pressure chamber 312 contains the first porous stainless steel plate 311, and three holes are formed in the upper pressure chamber 312 for fixing the upper long thermocouple 315, the upper short thermocouple 316, and the high-pressure air inlet pipe 317, respectively. An oil bath pipe 313 is installed between the pressure chamber 312 and the upper box body 314. Oil is introduced into the oil bath pipe 313 through the oil bath tank 33 to heat the upper pressure chamber 312. The temperature inside the upper pressure chamber 312 is monitored by the upper short thermocouple 316 and the upper long thermocouple 315 is monitored by the surface temperature of the sample 6. The data is transmitted to the data acquisition unit 34. Test gas is supplied to the upper pressure chamber 312 through the gas source 364, the pressure stabilizing container 362 and the high-pressure air inlet pipe 317, and the pressure inside the upper pressure chamber 312 is controlled. The pressure inside the upper pressure chamber 312 is monitored by the upper pressure sensor 318 and the data is transmitted to the data acquisition unit 34. Finally, the data is processed by the data processor 35.

[0053] In some possible embodiments, the lower box assembly 32 includes: a second porous stainless steel plate 321, the second porous stainless steel plate 321 having ventilation holes, and the top surface of the second porous stainless steel plate 321 abutting against the lower surface of the sample 6; a lower pressure chamber 322, the lower pressure chamber 322 having the second porous stainless steel plate 321 disposed inside; and a lower box body 323, the lower box body 323 being sleeved on the outside of the lower pressure chamber 322, the lower box body 323 and the upper box body 314 being connected by bolts, one side of the lower box body 323 being connected to the other end of the first support frame 42, and the other side of the lower box body 323 being connected to the other end of the upper support frame 42. The lower short thermocouple 324 is connected to the other end of the second support frame 43; the probe end of the lower short thermocouple 324 is located inside the lower pressure chamber 322, and the lead end of the lower short thermocouple 324 is connected to the data acquisition device 34; a low-pressure outlet pipe 325 is located at one end inside the lower pressure chamber 322, and the other end of the low-pressure outlet pipe 325 is connected to the vacuum pump 363; a lower pressure sensor 326 is located on the low-pressure outlet pipe 325 and is used to monitor the pressure inside the lower pressure chamber 322; the lower pressure sensor 326 is connected to the data acquisition device 34.

[0054] In this application, the lower box assembly 32 includes a second porous stainless steel plate 321, a lower pressure chamber 322, a lower box body 323, a lower short thermocouple 324, a low-pressure vent pipe 325, and a lower pressure sensor 326. The second porous stainless steel plate 321 is provided with vent holes and its top surface abuts against the lower surface of the sample 6. The sample 6 is supported by the first porous stainless steel plate 311 and the second porous stainless steel plate 321 to prevent the sample 6 from deforming due to the pressure difference between the upper pressure chamber 312 and the lower pressure chamber 322. The lower pressure chamber 322 is provided with the second porous stainless steel plate 321 inside, and two holes are opened at the bottom of the lower pressure chamber 322 for fixing the lower short thermocouple 324 and the low-pressure vent pipe 325. The temperature in the lower pressure chamber 322 is monitored by the lower short thermocouple 324, and the pressure in the lower pressure chamber 322 is monitored by the lower pressure sensor 326. The data is collected by the data acquisition device 34 and processed by the data processor 35.

[0055] Furthermore, to ensure the airtightness of the high-pressure sealing box, the bottom end of the upper pressure chamber 312 and the top end of the lower pressure chamber 322 press against both sides of the sample 6. O-ring seals 37 are provided on the outside of the upper pressure chamber 312 and the lower pressure chamber 322 to prevent gas from escaping. The upper box body 314 and the lower box body 323 are provided with matching screw holes, and the upper box body 314 and the lower box body 323 are fixedly connected by bolts, which facilitates the removal and placement of the sample 6. After the upper box body 314 and the lower box body 323 are fixedly sealed, the O-ring seals 37 on the outside of the upper pressure chamber 312 and the lower pressure chamber 322 will press against both sides of the sample 6, and a flexible protective sleeve 7 is wrapped around the outside of the upper box body 314 and the lower box body 323 to prevent heat loss. In a specific embodiment, the upper pressure chamber 312 is a cylindrical cavity with a diameter of 30 mm that can withstand 20 MPa high pressure, meets sealing requirements, and has a top diameter of 30 mm and a bottom diameter of 27 mm. The lower pressure chamber 322 is a T-shaped cavity with a top diameter of 30 mm and a bottom diameter of 27 mm that can withstand 20 MPa high pressure, meets sealing requirements, and has a top diameter of 30 mm and a bottom diameter of 27 mm. This is to maintain the stability and safety of the high-pressure penetration test. At the same time, in order to shorten the test time of the high-pressure penetration test, the T-shaped cavity of the lower pressure chamber 322 should be as small as possible. The vent holes on the first porous stainless steel plate 311 and the second porous stainless steel plate 321 are small and dense to ensure effective air permeability while preventing the sample 6 from being sucked into the vent holes under high pressure.

[0056] For some possible implementations, please refer to Figure 5 The fixing component 41 includes: a slide rail 411 fixed to the base plate 44; a first slider 412, one end of which is detachably connected to the slide rail 411 and the other end of which is detachably connected to the first clamp 21; and a second slider 413, one end of which is detachably connected to the slide rail 411 and the other end of which is detachably connected to the second clamp 22; wherein the first support frame 42 and the second support frame 43 are located between the first slider 412 and the second slider 413.

[0057] In this application, the fixing component 41 includes a slide rail 411, a first slider 412, and a second slider 413. The slide rail 411 is fixed to the base plate 44 by bolts, and the first slider 412 is fixed to the slide rail 411 by bolts. The first clamp 21 is fixed to the first slider 412. The position of the second slider 413 on the slide rail 411 is determined according to the distance between the first clamp 21 and the second clamp 22. The second slider 413 is fixed to the slide rail 411 by bolts, and the second clamp 22 is fixed to the second slider 413. The first slider 412 and the second slider 413 are at the same height, so that the sample 6 is horizontal. Furthermore, the first support frame 42 and the second support frame 43 can be positioned on the base plate 44 according to the cyclic tensile fatigue condition of the sample 6 and the installation condition of the high-pressure sealing box, so that the high-pressure sealing box is located in a place where the stress distribution of the sample 6 is uniform during the high-pressure permeation test.

[0058] Example 2

[0059] This invention provides a pressure-temperature-damage coupled air tightness testing method for flexible materials. The method utilizes the pressure-temperature-damage coupled air tightness testing system described in the first aspect to test the air tightness of the flexible material. The testing method includes: fabricating the flexible material into a dumbbell-shaped sample 6; fixing one end of the sample 6 to a first clamp 21 and the other end to a second clamp 22; fixing the first clamp 21 to a steel column 12 and the second clamp 22 to a tension transmission assembly 11; performing a cyclic tension test on the sample 6 using the tension transmission assembly 11 to obtain samples 6 with different degrees of fatigue damage; adjusting the position of one end of a second vertical rod 53 within a groove 54 on a horizontal rod 51 according to the distance between the first clamp 21 and the second clamp 22, so that the second vertical rod 53... The distance between the vertical rod 53 and the first vertical rod 52 is equal to the distance between the first clamp 21 and the second clamp 22. The first clamp 21 and the second clamp 22 are transferred from the tensile fatigue device 1 to the fixing assembly 41 and fixed by the lifting device 5. The fixing assembly 41 is fixed to the base plate 44, and the first support frame 42 and the second support frame 43 are fixed to the base plate 44, with the first support frame 42 and the second support frame 43 located below the central area of ​​the sample 6. The upper box assembly 31 and the lower box assembly 32 are connected by bolts, and the central area of ​​the sample 6 is located in the gap reserved between the upper box assembly 31 and the lower box assembly 32, so that the central area of ​​the sample 6 is completely sealed. A high-pressure penetration test is performed on the central area of ​​the sample 6 to detect the airtightness of the sample 6.

[0060] The high-pressure permeation test on the central region of the sample 6 includes: heating the temperature in the upper pressure chamber 312 to a preset temperature using an oil bath 33; controlling the vacuum pump 363 via the controller 361 to evacuate the lower pressure chamber 322 and the upper pressure chamber 312 respectively, until the pressure in the lower pressure chamber 322 remains constant after the vacuum pump 363 is turned off; controlling the gas source 364 and the pressure stabilizing container 362 via the controller 361, so that the gas in the gas source 364 is filtered and delivered to the upper pressure chamber 312 until the upper pressure chamber 312 reaches a preset pressure; acquiring the test parameters via the data acquisition unit 34 and the data processor 35 to calculate the gas permeability and gas permeability coefficient of the sample 6.

[0061] The formula for calculating the gas permeability (GTR) is as follows:

[0062] ;

[0063] in, The volume of the pressure chamber is expressed in cubic meters (m³). 3 T represents the temperature of the upper surface of sample 6, in Kelvin (K). The pressure of the test gas in the pressure chamber is expressed in Pascals (Pa); A is the gas permeation area, expressed in square meters (m²). 2 ); The pressure change in the lower pressure chamber per unit time is expressed in Pascals per second (Pa / s); R is the gas constant, 8.314 m. 3 •Pa / (K•mol;

[0064] The formula for calculating the gas permeability coefficient Q is:

[0065] ;

[0066] Where d is the thickness of sample 6, in meters (m); Q is the gas permeability coefficient, in molars per square meter per second (mol•m / (m²)). 2 •s•Pa)];GTR is the gas permeability, in moles per square meter per second in Pascals [mol / (m 2 •s•Pa)).

[0067] Specifically, this invention provides a pressure-temperature-damage coupled air tightness testing method for flexible materials, comprising the following steps:

[0068] (1) The flexible material is made into a dumbbell-shaped sample 6, such as Figure 6As shown; making the specimen 6 into a dumbbell-shaped plate can effectively prevent stress concentration at the end of the specimen 6, ensure that the stress distribution in the central area (5cm×5cm) of the specimen 6 is uniform, and the stress in the central area should be at the maximum value of the stress in the entire specimen 6, so that the damage and failure of the specimen 6 during cyclic tension fatigue will occur in the central area.

[0069] (2) Fix one end of the sample 6 to the first clamp 21 and the other end of the sample 6 to the second clamp 22 to fix the sample 6 and facilitate subsequent transfer.

[0070] (3) Fix the first clamp 21 to the steel column 12 and the second clamp 22 to the moving block 115 by bolts. Start the motor 112 to drive the servo cylinder 113 to move the push rod 119, which in turn drives the moving block 115 to make linear reciprocating motion along the guide rod 118, so as to cause the sample 6 to be tensioned cyclically. The servo cylinder 113 can be controlled by the tension control box to change the tension stroke and frequency of the push rod 119 in order to obtain samples 6 with different fatigue damage degrees.

[0071] (4) Adjust the position of one end of the second vertical rod 53 in the sliding groove 54 on the horizontal rod 51 according to the distance between the first clamp 21 and the second clamp 22, so that the distance between the second vertical rod 53 and the first vertical rod 52 is equal to the distance between the first clamp 21 and the second clamp 22. Transfer the first clamp 21 and the second clamp 22 from the tensile fatigue device 1 to the fixing assembly 41 and fix them by the lifting device 5.

[0072] (5) Fix the fixing component 41 to the base plate 44, fix the first support frame 42 and the second support frame 43 to the base plate 44, and the first support frame 42 and the second support frame 43 are located below the central area of ​​the sample 6.

[0073] (6) The upper box assembly 31 and the lower box assembly 32 are connected by bolts so that the central area of ​​the sample 6 is located in the gap reserved between the upper box assembly 31 and the lower box assembly 32, and sealed by the O-ring 37 so that the sample 6 is in close contact with the upper pressure chamber 312 and the lower pressure chamber 322, thereby ensuring that the central area (permeation area) of the sample 6 is completely sealed.

[0074] (7) Perform a high-pressure penetration test on the central region of sample 6, such as Figure 7As shown, open the oil bath 33 and heat the upper pressure chamber 312 to the preset temperature by adjusting the oil bath; close valves one, two, and three, open valves four and five, start the vacuum pump 363 to evacuate the gas in the lower pressure chamber 322, then close valve five, open valve two, and evacuate the gas in the upper pressure chamber 312, so that the central area of ​​the sample 6 can be tightly attached to the bottom surface of the first porous stainless steel plate 311 and the top surface of the second porous stainless steel plate 321. Continuous evacuation needs to be carried out for a sufficiently long time to ensure that the low-permeability sample 6 can completely expel all absorbed gas; close valves two and four to maintain the pressure of the upper pressure chamber 312 and the lower pressure chamber 322 at 10 Pa or lower, and turn off the vacuum pump 363 (e.g., If the pressure in the lower pressure chamber 322 begins to rise, there may be a gas leak or the absorbed gas may not have been completely discharged. The above steps need to be repeated to continue evacuating the vacuum. Based on the readings of pressure sensors P1 and P2, continuously adjust the pressure reducing valve until the reading of pressure sensor P2 is the same as the preset gas pressure. Stop adjusting the pressure reducing valve and keep the gas source 364 connected. Open valve one to allow the test gas in the gas source 364 to pass through the filter to remove impurities and enter the pressure stabilizing container 362. After opening the valve of the pressure stabilizing container 362, introduce the purified test gas into the upper pressure chamber 312 until the pressure reaches the preset pressure. Close valve one to stop the supply of test gas and collect the data in the upper pressure chamber 312 and lower pressure chamber 322 through the data acquisition device 34.

[0075] When the pressure in the lower pressure chamber 322 begins to increase, it indicates that the test gas has permeated from the upper pressure chamber 312 into the lower pressure chamber 322. Record the pressure in the upper pressure chamber 312 at this time. The temperature T of the upper surface of sample 6; simultaneously, data from the lower pressure chamber 322 are collected, including the pressure collected by the lower pressure sensor 326 in the lower pressure chamber 322. The vertical axis represents time. Plot the gas permeation curve with the x-axis as the horizontal axis, as shown below. Figure 8 As shown, A1 is the initial linear segment, and A2 is the later saturation segment. Then, the gas permeability GTR and gas permeability coefficient Q are calculated based on the collected data. In order to reduce the inaccuracy of test results caused by the random error of a single sample 6 and improve the reliability of test results, each complete test must be carried out using 3 standard samples 6.

[0076] Following the steps described above, data on sample 6 under different temperatures, pressures, and fatigue damage conditions can be obtained, thereby calculating the gas permeability and gas permeability coefficient of sample 6 to achieve the airtightness test of sample 6.

[0077] It should be noted that since this second embodiment and the first embodiment are embodiments under the same inventive concept and their structures are completely identical, the structures in the second embodiment that are substantially the same as those in the first embodiment will not be described in detail. For the parts not described in detail, please refer to the first embodiment.

[0078] In summary, this invention addresses the issue of airtightness of flexible materials under different air pressures, temperatures, and fatigue damage levels. It proposes an innovation to conventional flexible material airtightness testing systems, employing a system combining high-pressure infiltration, thermal cycling, and tensile fatigue testing to study the effects of different air pressures, temperatures, and damage levels on the airtightness of flexible materials. To ensure effective system integration, the high-pressure infiltration device utilizes a high-pressure sealed box composed of an upper and lower box assembly. An oil bath pipe is installed outside the upper pressure chamber of the upper box assembly to achieve different temperature conditions. During cyclic tensioning of the specimen in the tensile fatigue device, bolts are loosened to separate the upper and lower box assemblies. After tensioning, the clamps at both ends of the specimen are lifted and fixed to the first and second sliders. The specimen is then placed into the infiltration area of ​​the high-pressure sealed box using detachable first and second support frames. Finally, bolts are tightened to seal the upper and lower box assemblies, and the airtightness of the specimen is tested. The entire test process involves first cyclically tensioning the sample and then conducting an airtightness test. During the airtightness test, the oil bath circulation device is turned on, and the temperature of the upper pressure chamber can be adjusted. After completing the entire test process, the tensioning frequency and stroke of the tensile fatigue device are changed to perform cyclic tensioning again, so that the sample reaches the set fatigue damage level. Then, the air pressure and the temperature of the upper pressure chamber are adjusted according to the test plan to conduct an airtightness test. By repeating this operation, the gas permeability and gas permeability coefficient of the flexible material under different air pressures, temperatures, and damage conditions can be calculated. This can effectively reproduce actual engineering conditions and evaluate the airtightness and fatigue resistance of the flexible material.

[0079] Finally, it should be noted that the above embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the scope of the technology disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. All should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0080] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A pressure-temperature-damage coupled air tightness testing system for flexible materials, characterized in that, The test system includes: A tensile fatigue device includes a tensile transmission assembly and a steel column, wherein the steel column is fixed to one end of the tensile transmission assembly. The sample holder includes a first clamp and a second clamp. The first clamp is detachably connected to the steel column and is used to clamp one end of the sample. The second clamp is detachably connected to the other end of the tensile transmission assembly and is used to clamp the other end of the sample. A high-pressure permeation device includes a high-pressure sealed box consisting of an upper box assembly and a lower box assembly. A gap is reserved between the upper box assembly and the lower box assembly to accommodate the central area of ​​the sample. The upper box assembly and the lower box assembly are connected by bolts. A fixed support device includes a fixing component, a first support frame, a second support frame, and a base plate. The fixing component is fixed to the base plate, one end of the fixing component is detachably connected to a first clamp, and the other end of the fixing component is detachably connected to a second clamp. One end of the first support frame is fixedly connected to the base plate, and the other end of the first support frame is connected to one side of the lower box assembly. One end of the second support frame is fixedly connected to the base plate, and the other end of the second support frame is connected to the other side of the lower box assembly. The lifting device includes a horizontal bar, a first vertical bar, and a second vertical bar. One end of the horizontal bar is provided with a sliding groove. One end of the first vertical bar is fixedly connected to the other end of the horizontal bar, and the other end of the first vertical bar is detachably connected to the first clamp. One end of the second vertical bar is slidably connected to the sliding groove, and the other end of the second vertical bar is detachably connected to the second clamp.

2. The air pressure-temperature-damage coupled flexible material airtightness testing system according to claim 1, characterized in that, The tension transmission assembly includes: Platform board and motor, A servo electric cylinder is vertically fixed to one end of the platform plate via a cylinder support; the servo electric cylinder is connected to the motor. A baffle, which is vertically fixed to the other end of the platform plate; A movable block is disposed between the servo cylinder and the baffle. The movable block is detachably connected to the second clamp. Bearings and pressure sensor seats are spaced apart on the movable block. A guide rod, one end of which is fixedly connected to the steel column, and the other end of which passes through the bearing and is fixedly connected to the baffle. A push rod, one end of which is fixedly disposed inside the servo electric cylinder, and the other end of which is fixedly connected to the pressure sensor seat.

3. The air pressure-temperature-damage coupled flexible material airtightness testing system according to claim 2, characterized in that, The tensile fatigue device further includes: A tension control box is communicatively connected to the motor and is used to control the operating status of the servo cylinder.

4. The air pressure-temperature-damage coupled flexible material airtightness testing system according to claim 1, characterized in that, The high-pressure permeation device also includes: An oil bath tank, which is connected to the upper box assembly, is used to adjust the temperature inside the upper box assembly; A data acquisition unit is used to collect pressure and temperature data within the upper and lower box assemblies. A data processor is used to process the pressure and temperature collected by the data acquisition device to obtain the gas permeability and gas permeability coefficient of the sample. The permeation control box includes a controller, a pressure stabilizing container, a vacuum pump, and a gas source. One end of the pressure stabilizing container is connected to the gas source, and the other end of the pressure stabilizing container is connected to the upper box assembly. The vacuum pump is used to remove gas from the upper box assembly and the lower box assembly. The controller is communicatively connected to the pressure stabilizing container, the vacuum pump, and the gas source.

5. The air pressure-temperature-damage coupled flexible material air tightness testing system according to claim 4, characterized in that, The upper box assembly includes: A first porous stainless steel plate, wherein the first porous stainless steel plate is provided with vent holes, and the bottom surface of the first porous stainless steel plate abuts against the upper surface of the sample. The upper pressure chamber is provided with the first porous stainless steel plate inside the upper pressure chamber; An oil bath pipe is provided outside the upper pressure chamber and is connected to the oil bath tank to adjust the temperature inside the upper pressure chamber. The upper box body is sleeved on the outside of the oil bath pipe, and the upper box body and the lower box assembly are connected by bolts; An upper long thermocouple, wherein the probe end of the upper long thermocouple is located on the upper surface of the sample, and the lead end of the upper long thermocouple is connected to the data acquisition device; An upper short thermocouple, wherein the probe end of the upper short thermocouple is located inside the upper pressure chamber, and the lead end of the upper short thermocouple is connected to the data acquisition device; A high-pressure air inlet pipe, one end of which is located inside the upper pressure chamber, and the other end of which is connected to the pressure stabilizing container; An upper pressure sensor is located on the high-pressure intake pipe and is used to monitor the pressure in the upper pressure chamber; the upper pressure sensor is connected to the data acquisition unit.

6. The air pressure-temperature-damage coupled flexible material air tightness testing system according to claim 5, characterized in that, The lower box assembly includes: A second porous stainless steel plate is provided with vent holes, and the top surface of the second porous stainless steel plate abuts against the lower surface of the sample. The lower pressure chamber is provided with the second porous stainless steel plate inside the lower pressure chamber; The lower box body is sleeved outside the lower pressure chamber. The lower box body and the upper box body are connected by bolts. One side of the lower box body is connected to the other end of the first support frame, and the other side of the lower box body is connected to the other end of the second support frame. A lower short thermocouple, wherein the probe end of the lower short thermocouple is located inside the lower pressure chamber, and the lead end of the lower short thermocouple is connected to the data acquisition unit; A low-pressure outlet pipe, one end of which is located inside the lower pressure chamber, and the other end of which is connected to the vacuum pump; A pressure sensor is located on the low-pressure outlet pipe and is used to monitor the pressure in the pressure chamber; the pressure sensor is connected to the data acquisition unit.

7. The air pressure-temperature-damage coupled flexible material airtightness testing system according to claim 1, characterized in that, The fixing component includes: A slide rail, which is fixed to the base plate; A first slider, one end of which is detachably connected to the slide rail, and the other end of which is detachably connected to the first clamp; The second slider has one end detachably connected to the slide rail and the other end detachably connected to the second clamp. The first support frame and the second support frame are located between the first slider and the second slider.

8. A method for testing the airtightness of flexible materials using a pressure-temperature-damage coupled airtightness testing system as described in any one of claims 1-7, characterized in that, The test method includes: The flexible material was fabricated into dumbbell-shaped pellets. One end of the sample is fixed to the first clamp, and the other end of the sample is fixed to the second clamp; The first clamp is fixed to the steel column, and the second clamp is fixed to the tensile transmission assembly. The sample is subjected to cyclic tensioning test through the tensile transmission assembly to obtain samples with different degrees of fatigue damage. Adjust the position of one end of the second vertical rod in the groove on the horizontal bar according to the distance between the first clamp and the second clamp, so that the distance between the second vertical rod and the first vertical rod is equal to the distance between the first clamp and the second clamp. Then, use the lifting device to transfer the first clamp and the second clamp from the tensile fatigue device to the fixing assembly and fix them. The fixing assembly is fixed to the base plate, the first support frame and the second support frame are fixed to the base plate, and the first support frame and the second support frame are located below the central region of the sample; The upper box assembly and the lower box assembly are connected by bolts, and the central area of ​​the sample is located in the gap reserved between the upper box assembly and the lower box assembly, so that the central area of ​​the sample is completely sealed. A high-pressure permeation test was performed on the central region of the sample to detect its airtightness.

9. The airtightness testing method for flexible materials based on pressure-temperature-damage coupling according to claim 8, characterized in that, High-pressure permeation testing of the central region of the sample includes: The temperature inside the upper pressure chamber is heated to the preset temperature using an oil bath. The vacuum pump is controlled by the controller to evacuate the lower pressure chamber and the upper pressure chamber respectively. After the vacuum pump is turned off, the pressure in the lower pressure chamber remains unchanged. The controller controls the gas source and pressure stabilizing container, so that the gas in the gas source is filtered and delivered to the upper pressure chamber until the upper pressure chamber reaches the preset pressure. Test parameters are acquired using a data acquisition unit and a data processor to calculate the gas permeability and gas permeability coefficient of the sample.

10. The airtightness testing method for flexible materials based on pressure-temperature-damage coupling according to claim 9, characterized in that, The formula for calculating the gas permeability (GTR) is as follows: ; in, Let T be the volume of the pressure chamber and T be the temperature of the upper surface of the sample. The pressure of the test gas in the pressure chamber is given by [insert pressure here], and A is the gas permeation area. R represents the pressure change per unit time in the lower pressure chamber, where R is the gas constant. The formula for calculating the gas permeability coefficient Q is: ； Where d is the thickness of the sample.

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