Method, device and system for testing air tightness of load cabin

Abstract

The invention relates to the field of testing, and discloses a load cabin air tightness testing method, device and system, and the method comprises the steps: obtaining a load cabin model constructed based on multi-physics field simulation, a plurality of groups of pressure drop fitting curves under different simulation initial air pressures of the load cabin model obtained through simulation testing, and a plurality of groups of corresponding air pressure change rule curves under variable temperature conditions; a pressurization test and a pressure maintaining test are conducted on the entity load cabin, and the actually-measured initial pressure, the actually-measured initial temperature and the actually-measured pressure, the actually-measured temperature and the actually-measured pressure drop corresponding to different pressure maintaining test durations are obtained; analyzing a plurality of groups of pressure drop fitting curves and a plurality of groups of air pressure change rule curves under variable temperature conditions, and determining theoretical pressure drops under corresponding pressure maintaining test durations in combination with a Lagrange interpolation method; and when the actually measured pressure drop does not exceed the theoretical pressure drop, determining that the air tightness of the entity load cabin is normal, otherwise, determining that the air tightness is abnormal. The test cost is reduced, the test efficiency is improved, the test is not limited by the environment temperature condition any more, and the test flexibility is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air tightness testing, and in particular to a load compartment air tightness testing method, device and system. Background Art

[0002] The photoelectric turntable is a high-precision video monitoring, identification, locking and tracking device. It is equipped with an infrared thermal imager and a high-definition visible light camera, which can observe targets within a radius of 15 kilometers. It integrates optics, electricity and mechanical structures, and is a high-end video monitoring device.

[0003] Photoelectric turntables are widely used in military and civilian fields. As the application environment becomes more complex and changeable, turntables are often required to have "dust-proof, rain-proof, and salt-fog-proof" functions. The airtight design of the load compartment of the photoelectric turntable is a key technology to ensure that the turntable can maintain internal gas sealing and prevent external gas from entering the interior under specific working conditions. Good sealing can ensure the stable operation of the photoelectric turntable in harsh environments.

[0004] In order to ensure that the optoelectronic turntable can work stably and reliably in various harsh environments, it is particularly important to test the air tightness of its load chamber. The pressure holding time refers to the time it takes for the pressure in the load chamber to drop to the ambient pressure or other limited pressure after the working pressure in the load chamber is set to be greater than the ambient pressure so that the outside gas cannot enter the load chamber.

[0005] In terms of existing technologies, airtightness testing mainly relies on the pressure decay method or the mass flow method. The pressure decay method determines the sealing performance of the tested component by measuring the pressure change within a given time; while the mass flow method determines the sealing performance of the tested component by measuring the gas flow rate under constant pressure. These technologies usually require the use of high-precision pressure sensors and flow meters to ensure the accuracy of the test results.

[0006] However, there are still some problems in the air tightness test of the load chamber of the photoelectric turntable. The load chamber air tightness test mainly tests whether the pressure holding time of the photoelectric turntable meets the requirements. If only experimental testing is performed, the test time is usually long. Secondly, the test process may be affected by the ambient temperature, resulting in unstable results, which not only increases the test cost, but also affects the R&D cycle. Therefore, traditional testing methods may not meet the needs, and further research and exploration of new testing methods are needed. Summary of the invention

[0007] Based on this, it is necessary to provide a load compartment air tightness testing method, device and system to address the existing problems, aiming to reduce testing costs, improve testing efficiency, no longer be limited by ambient temperature conditions, and improve testing flexibility.

[0008] A first aspect of the present application provides a load compartment air tightness testing method, which comprises:

[0009] Obtain a load compartment model constructed based on multi-physics field simulation and obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure change law curves under variable temperature conditions through simulation tests;

[0010] Perform pressurization test and pressure holding test on the physical load chamber to obtain the measured initial pressure, measured initial temperature, and the measured pressure, measured temperature and measured pressure drop corresponding to different pressure holding test durations;

[0011] According to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test duration, the multiple groups of pressure drop fitting curves and the multiple groups of pressure change law curves under the variable temperature conditions are analyzed, and the theoretical pressure drop under the corresponding pressure holding test duration is determined in combination with the Lagrange interpolation method;

[0012] When the measured pressure drop does not exceed the theoretical pressure drop, the airtightness of the physical load compartment is determined to be normal; otherwise, the airtightness of the physical load compartment is determined to be abnormal.

[0013] In some embodiments, the pressure drop fitting curve is used to characterize the change pattern of the air pressure in the load compartment model over time; the air pressure change law curve under variable temperature conditions is used to characterize the change pattern of the air pressure of the load compartment model at different temperatures with the initial air pressure used by the pressure drop fitting curve as the corresponding initial value; the measured pressure drop is used to characterize the actual pressure relief rate of the physical load compartment.

[0014] In some embodiments, each set of the pressure drop fitting curves meets the pressure holding time requirement of the physical load compartment and the initial air pressure of each set of the pressure drop fitting curves meets the air pressure requirement of the physical load compartment.

[0015] In some embodiments, the analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test duration includes:

[0016] Based on the multiple groups of pressure drop fitting curves, a pressure drop comparison table is constructed; wherein the pressure drop comparison table is used to obtain the pressure drop value per unit time of the load compartment model in multiple groups of simulation tests under constant temperature simulation tests with multiple different initial air pressures as the test starting point, and the average unit time change rate of the pressure in the load compartment model in the corresponding group;

[0017] Based on the measured initial pressure, query the pressure drop comparison table to determine a first group of simulation data corresponding to a group of pressure drop fitting curves adjacent to the measured initial pressure, and a second group of simulation data adjacent to the first group of simulation data;

[0018] Based on the measured pressure under the corresponding pressure holding test duration, the first group of simulation data and the second group of simulation data are queried to determine the adjacent pressure adjacent to the measured pressure, the similar pressure adjacent to the adjacent pressure, and the corresponding average unit time change rate of the adjacent pressure and the average unit time change rate of the similar pressure, the measured pressure is between the adjacent pressure and the similar pressure.

[0019] In some embodiments, the analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test duration, further includes:

[0020] Based on the multiple groups of pressure change law curves under variable temperature conditions, a table of the influence of temperature on the air pressure in the load compartment model under a closed state is constructed; wherein the table of the influence of temperature on the air pressure in the load compartment model under a closed state is used to obtain the pressure drop value corresponding to each unit temperature change of the load compartment model in each group of tests under the sealing simulation test, taking the multiple initial air pressures in the pressure drop comparison table as the test starting point, and the average temperature change rate of the pressure in the load compartment model in the corresponding group;

[0021] According to the measured temperature, query the table of the influence of temperature on the air pressure in the load compartment model under the closed state to determine the adjacent temperature and the similar temperature adjacent to the measured temperature;

[0022] Based on the measured initial pressure, a table of the influence of temperature on the air pressure in the load compartment model under the closed state is queried to determine a first data group corresponding to a set of air pressure change law curves under variable temperature conditions adjacent to the measured initial pressure and an adjacent average temperature change rate; as well as a second data group corresponding to another set of air pressure change law curves under variable temperature conditions adjacent to the first data group and an adjacent average temperature change rate.

[0023] In some embodiments, the method of combining the Lagrange interpolation method to determine the theoretical pressure drop corresponding to the pressure holding test duration includes:

[0024] Based on the measured pressure, adjacent pressure, similar pressure, average rate of change of adjacent pressure per unit time, average rate of change of similar pressure per unit time, combined with the Lagrange interpolation method, the pressure drop rate of equivalent pressure is determined;

[0025] Based on the measured temperature, adjacent temperature, similar temperature, average change rate of adjacent temperature, average change rate of similar temperature, combined with Lagrange interpolation method, the equivalent temperature pressure drop rate is determined;

[0026] Based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate, the theoretical pressure drop under the corresponding pressure holding test time is determined.

[0027] In some embodiments, determining the theoretical pressure drop corresponding to the pressure holding test duration based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate includes:

[0028] Equivalent pressure drop rate = ((measured pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average rate of change of adjacent pressure per unit time + ((actual pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average hourly rate of change of adjacent pressure;

[0029] Equivalent temperature pressure drop rate = ((measured temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature + ((actual temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature;

[0030] Theoretical pressure drop = equivalent pressure drop rate + equivalent temperature pressure drop rate.

[0031] In some embodiments, the pressurization test of the physical load compartment includes:

[0032] The physical load compartment is connected to the booster pump through a connecting pipeline, wherein the connecting pipeline is provided with a pressure gauge for testing the inflation pressure and an on-off control valve for controlling the inflation on and off;

[0033] Start the booster pump to increase the pressure and slowly increase it to the target initial pressure, ensuring that the boosting time does not exceed 5 minutes;

[0034] After the air pressure in the physical load compartment is stabilized, the on-off control valve is closed to obtain the measured initial pressure value and the measured initial temperature.

[0035] A second aspect of the present application provides a load compartment air tightness testing device, comprising:

[0036] A simulation module is used to obtain a load compartment model constructed based on multi-physics field simulation and to obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure change law curves under variable temperature conditions through simulation tests;

[0037] The physical test module is used to perform a pressurization test and a pressure-maintaining test on the physical load compartment to obtain the measured initial pressure, the measured initial temperature, and the measured pressure, the measured temperature, and the measured pressure drop corresponding to different pressure-maintaining test durations;

[0038] A test analysis module, for analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test time, and combining the Lagrange interpolation method to determine the theoretical pressure drop under the corresponding pressure holding test time;

[0039] The result judgment module is used to judge that the airtightness of the physical load compartment is normal when the measured pressure drop does not exceed the theoretical pressure drop, otherwise, it is judged that the airtightness of the physical load compartment is abnormal.

[0040] A third aspect of the present application provides a load compartment air tightness testing system, wherein the load compartment air tightness testing system comprises the method mentioned in any one of the above embodiments, for performing an air tightness test on a physical load compartment.

[0041] Beneficial effects of the present invention:

[0042] In the load compartment air tightness test method of the present invention, the air tightness test of the physical load compartment is combined with the simulation test of the load compartment model. By comparing the relationship between the measured pressure drop and the theoretical pressure drop, it can be quickly determined whether the air tightness of the physical load compartment is normal.

[0043] Specifically, it first obtains a load cabin model constructed based on multi-physical field simulation and obtains multiple groups of pressure drop fitting curves of the load cabin model under different simulation initial air pressures and corresponding multiple groups of air pressure change law curves under variable temperature conditions through simulation tests; then, a pressurization test and a pressure holding test are performed on the physical load cabin to obtain the measured initial pressure, the measured initial temperature, and the corresponding measured pressure, measured temperature and measured pressure drop under different pressure holding test durations; then, according to the measured initial pressure and the measured pressure and measured temperature under the corresponding pressure holding test duration, the multiple groups of pressure drop fitting curves and the multiple groups of air pressure change law curves under variable temperature conditions are analyzed, and the theoretical pressure drop under the corresponding pressure holding test duration is determined in combination with the Lagrange interpolation method; finally, when the measured pressure drop does not exceed the theoretical pressure drop, it is determined that the airtightness of the physical load cabin is normal, otherwise, it is determined that the airtightness of the physical load cabin is abnormal.

[0044] Therefore, by comparing the relationship between the measured pressure drop and the theoretical pressure drop, it can quickly determine whether the airtightness of the physical load compartment is normal, which can greatly reduce the time requirements for the airtightness test of the physical load compartment, thereby reducing the test cost and improving the test efficiency. At the same time, the pressure change law curve under the variable temperature conditions of the simulation test can be used to analyze the impact of ambient temperature changes on the test pressure, so as to provide a reference for the airtightness test of the physical load compartment, so it is no longer limited by ambient temperature conditions, and improves the flexibility of the test. In summary, it has the advantages of simple test methods, high environmental adaptability, lower cost, and short test cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without paying creative work.

[0046] Figure 1 A schematic flow chart of a load compartment air tightness testing method provided for an embodiment of the present application;

[0047] Figure 2 Schematic diagram of the actual airtightness test platform provided for the implementation of the present application. DETAILED DESCRIPTION

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0049] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0050] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present invention, unless otherwise clearly specified and limited, a feature "above" or "below" a second feature may be in direct contact with the second feature, or in indirect contact with the second feature through an intermediate medium. Moreover, a feature "above", "above" and "above" a second feature may mean that the feature is directly above or obliquely above the second feature, or simply means that the feature is higher in level than the second feature. A feature "below", "below" and "below" a second feature may mean that the feature is directly below or obliquely below the second feature, or simply means that the feature is lower in level than the second feature.

[0053] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0054] refer to Figure 1 , an embodiment of the present application provides a load compartment air tightness testing method, which includes:

[0055] Step 100, obtaining a load compartment model constructed based on multi-physics field simulation and performing simulation tests to obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure variation curves under variable temperature conditions;

[0056] Step 200: Perform a pressurization test and a pressure-maintaining test on the physical load compartment to obtain the measured initial pressure, the measured initial temperature, and the measured pressure, the measured temperature, and the measured pressure drop corresponding to different pressure-maintaining test durations;

[0057] Step 300: Analyze the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test time, and determine the theoretical pressure drop under the corresponding pressure holding test time by combining the Lagrange interpolation method;

[0058] Step 400: When the measured pressure drop does not exceed the theoretical pressure drop, it is determined that the airtightness of the physical load compartment is normal; otherwise, it is determined that the airtightness of the physical load compartment is abnormal.

[0059] Specifically, in some embodiments, the pressure drop fitting curve is used to characterize the law of change of air pressure in the load compartment model over time; the air pressure change law curve under variable temperature conditions is used to characterize the law of change of air pressure in the load compartment model at different temperatures with the initial air pressure adopted by the pressure drop fitting curve as the corresponding initial value; the measured pressure drop is used to characterize the actual pressure relief speed of the physical load compartment. In some embodiments, each group of the pressure drop fitting curves meets the pressure holding time requirement of the physical load compartment and the initial air pressure of each group of the pressure drop fitting curves meets the air pressure requirement of the physical load compartment, thereby enabling the simulation test to more accurately simulate and feedback the pressure change characteristics of the physical load compartment during the airtight test.

[0060] In the load compartment air tightness test method of the embodiment of the present application, the air tightness test of the physical load compartment is combined with the simulation test of the load compartment model. By comparing the relationship between the measured pressure drop and the theoretical pressure drop, it is possible to quickly determine whether the air tightness of the physical load compartment is normal. Therefore, it is not necessary to rely solely on the air tightness test of the physical load compartment to conduct a complete ultra-long test. By referring to the theoretical pressure drop, it is possible to quickly find out whether it is abnormal, thereby greatly reducing the time requirement for the air tightness test of the physical load compartment, reducing the test cost, and improving the test efficiency; at the same time, the pressure change law curve under the variable temperature conditions of the simulation test can be used to analyze the impact of the ambient temperature change on the test pressure, so as to provide a reference for the air tightness test of the physical load compartment, so it is no longer limited by the ambient temperature conditions, and the flexibility of the test is improved.

[0061] The following will introduce in detail how to combine the Lagrange interpolation method to determine the theoretical pressure drop under the corresponding pressure holding test duration based on the measured initial pressure, the measured pressure under the corresponding pressure holding test duration, the measured temperature, and multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under the said variable temperature conditions.

[0062] In some embodiments, the step 300 analyzes the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure under the corresponding pressure holding test duration, and the measured temperature, including:

[0063] Step 310: construct a pressure drop comparison table based on the multiple groups of pressure drop fitting curves; wherein the pressure drop comparison table is used to obtain the pressure drop value per unit time of the load compartment model in multiple groups of simulation tests under constant temperature simulation tests with multiple different initial air pressures as the test starting points, and the average unit time change rate of the pressure in the load compartment model in the corresponding group;

[0064] Step 320: based on the measured initial pressure, query the pressure drop comparison table to determine a first group of simulation data corresponding to a group of pressure drop fitting curves adjacent to the measured initial pressure, and a second group of simulation data adjacent to the first group of simulation data;

[0065] Step 330: Based on the measured pressure under the corresponding pressure holding test duration, query the first group of simulation data and the second group of simulation data to determine the adjacent pressure adjacent to the measured pressure, the similar pressure adjacent to the adjacent pressure, and the corresponding average unit time change rate of the adjacent pressure and the average unit time change rate of the similar pressure, the measured pressure is between the adjacent pressure and the similar pressure.

[0066] Illustratively, a pressure drop comparison table may be constructed as shown in Table 1 - Pressure drop comparison table (constant temperature).

[0067] Table 1 - Pressure drop comparison table (constant temperature)

[0068]

[0069]

[0070] The pressure drop value in Table 1 is equal to the previous reading minus the next reading, for example, a4 = Y 13 -Y 14 The average unit time change rate can be the average hourly change rate, that is, the average change in pressure per hour. For example Y l0 represents the adjacent simulation initial pressure in the simulation data corresponding to the measured initial pressure of the physical test determined by looking up the table, Y j0 represents the adjacent simulation initial pressure corresponding to the measured initial pressure of the physical test in the simulation data determined by looking up the table; Y l0 and Y j0 They can correspond to Y1 to Y n For example, if the measured initial pressure is 20 MPa, Y l0 It can be 18Mpa, Y j0 It can be 22Mpa. Table 1 records n groups of simulation data corresponding to n groups of pressure drop fitting curves. The adjacent pressures adjacent to the measured pressure and the pressures close to the adjacent pressures can be found in the simulation data of the determined corresponding group. The adjacent pressures can be expressed by Y l Indicates that similar pressure can be used Y j Indicates that, for example, after searching, Y l =Y l5 ; Y j =Y j6 .

[0071] In some embodiments, the step 300 includes analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure under the corresponding pressure holding test duration, and the measured temperature, and further includes:

[0072] Step 340: construct a table of the influence of temperature on the air pressure in the load compartment model under a closed state based on the multiple groups of pressure change law curves under variable temperature conditions; wherein the table of the influence of temperature on the air pressure in the load compartment model under a closed state is used to obtain the pressure drop value corresponding to each unit temperature change of the load compartment model in each group of tests under the sealing simulation test and the average temperature change rate of the pressure in the load compartment model in the corresponding group, taking the multiple initial air pressures in the pressure drop comparison table as the test starting point;

[0073] Step 350: According to the measured temperature, query the table of the influence of the temperature on the air pressure in the load compartment model in the closed state to determine the adjacent temperature and the similar temperature adjacent to the measured temperature;

[0074] Step 360: Based on the measured initial pressure, query the table of the influence of the temperature on the air pressure in the load compartment model under the closed state, and determine a first data group corresponding to a set of air pressure change law curves under variable temperature conditions adjacent to the measured initial pressure and the adjacent average temperature change rate; and a second data group corresponding to another set of air pressure change law curves under variable temperature conditions adjacent to the first data group and the adjacent average temperature change rate.

[0075] Explanatory table of the effect of temperature on the air pressure in the load compartment model under a closed state can be shown in Table 2 - Effect of temperature on the air pressure in the load compartment model under a closed state.

[0076] Table 2 - Effect of temperature on air pressure in load compartment model under closed state

[0077]

[0078] The temperature difference effect in Table 2 is equal to the previous reading minus the next reading, for example, W 11 =Y1-Y 11 ; The average temperature change rate is equal to the average value of the temperature difference effect, for example Each column of readings and its corresponding temperature difference influence column in Table 2 corresponds to a set of pressure change law curves under variable temperature conditions, that is, a set of data groups. Table 2 provides statistics of n sets of data groups corresponding to n sets of pressure change law curves under variable temperature conditions. wl represents the adjacent temperature adjacent to the measured temperature; Y wj Indicates the temperature close to the adjacent temperature. The measured temperature can be expressed by Y wsIndicates; by looking up the table, the corresponding rows of adjacent temperatures and similar temperatures can be determined; then by similar simulation initial pressure Y j0 and the initial pressure Y of the adjacent simulation l0 , the corresponding adjacent average temperature change rate Y can be determined wlv and the average rate of change of similar temperature Y wjv .

[0079] In some embodiments, the step 300 combines the Lagrange interpolation method to determine the theoretical pressure drop corresponding to the pressure holding test duration, including:

[0080] Step 370: Determine the pressure drop rate of the equivalent pressure based on the measured pressure, the adjacent pressure, the similar pressure, the average rate of change of the adjacent pressure per unit time, and the average rate of change of the similar pressure per unit time in combination with the Lagrange interpolation method;

[0081] Step 380, based on the measured temperature, adjacent temperature, similar temperature, average change rate of adjacent temperature, average change rate of similar temperature, combined with Lagrange interpolation method, determine the equivalent temperature pressure drop rate;

[0082] Step 390: Determine the theoretical pressure drop corresponding to the pressure holding test duration based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate.

[0083] Specifically, the relevant calculations can be completed by looking up Table 1 and Table 2 above, and the theoretical pressure drop can be finally determined, and the details will not be repeated here.

[0084] In some embodiments, determining the theoretical pressure drop corresponding to the pressure holding test duration based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate in step 390 includes:

[0085] Equivalent pressure drop rate = ((measured pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average rate of change of adjacent pressure per unit time + ((actual pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average hourly rate of change of adjacent pressure;

[0086] Equivalent temperature pressure drop rate = ((measured temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature + ((actual temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature;

[0087] Theoretical pressure drop = equivalent pressure drop rate + equivalent temperature pressure drop rate.

[0088] Through the above calculation method based on Lagrange interpolation method, the theoretical pressure drop under normal conditions can be deduced, and then combined with the theoretical pressure drop to analyze whether the measured pressure drop is normal, so as to judge whether the air tightness of the physical load compartment is normal during the air tightness test.

[0089] Further, in some embodiments, the pressurization test of the physical load compartment in step 200 includes:

[0090] Step 210, connecting the physical load cabin to the booster pump through a connecting pipeline, wherein the connecting pipeline is provided with a pressure gauge for testing the inflation pressure and an on-off control valve for controlling the inflation on and off;

[0091] Step 220, start the booster pump to start boosting, and slowly increase the pressure to the target initial pressure, ensuring that the boosting time does not exceed 5 minutes;

[0092] Step 230: After the air pressure in the physical load compartment is stabilized, close the on-off control valve to obtain the measured initial pressure value and the measured initial temperature.

[0093] Explanatory, for reference Figure 2 , Figure 2 This is a schematic diagram of the actual measurement airtight test platform. In some embodiments, the actual measurement airtight test platform includes a physical load compartment 1, a load compartment inflation valve 2, a load compartment inflation nozzle 3, a three-way connector 4, an inflation pressure gauge 5, a shut-off valve 6, and a compressed air pump 7.

[0094] In summary, the load compartment air tightness testing method provided by the embodiments of the present application has the following advantages:

[0095] Simple test method: By combining simulation and experiment, the complex test process can be simplified. Simulation can simulate conditions that are difficult to achieve in the real environment, while the experiment can verify the accuracy of the simulation. The two complement each other, making the entire test process more efficient and simple;

[0096] High environmental adaptability: This test method has strong environmental adaptability and has lower requirements for test conditions. If the external environment changes during the test, we can simulate these conditions through simulation to test the air tightness of the load compartment of the photoelectric turntable. This makes our test no longer limited by the environmental conditions of the laboratory, greatly improving the flexibility of the test.

[0097] Lower cost: Compared with traditional testing methods, this test method that combines simulation and testing can greatly reduce testing costs. On the one hand, the use of simulation software does not require expensive test equipment, which reduces hardware costs. On the other hand, simulation can detect potential problems in advance and reduce the cost of trial and error in the test.

[0098] Short test cycle: Due to the combination of simulation and experiment, multiple test scenarios can be simulated and verified in a short time, greatly shortening the test cycle.

[0099] In addition, an embodiment of the present application further provides a load compartment air tightness testing device, which includes:

[0100] A simulation module is used to obtain a load compartment model constructed based on multi-physics field simulation and to obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure change law curves under variable temperature conditions through simulation tests;

[0101] The physical test module is used to perform a pressurization test and a pressure-maintaining test on the physical load compartment to obtain the measured initial pressure, the measured initial temperature, and the measured pressure, the measured temperature, and the measured pressure drop corresponding to different pressure-maintaining test durations;

[0102] A test analysis module, for analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test time, and combining the Lagrange interpolation method to determine the theoretical pressure drop under the corresponding pressure holding test time;

[0103] The result judgment module is used to judge that the airtightness of the physical load compartment is normal when the measured pressure drop does not exceed the theoretical pressure drop, otherwise, it is judged that the airtightness of the physical load compartment is abnormal.

[0104] It should be noted that the load compartment air tightness testing device can be an automated testing device or a semi-automated device that requires testers to participate in one or more processes. There is no specific limitation. It only needs to be able to complete the load compartment air tightness testing method mentioned in any of the above-mentioned embodiments.

[0105] In addition, an embodiment of the present application further provides a load compartment air tightness testing system, which includes the method mentioned in any of the above embodiments for performing an air tightness test on a physical load compartment, and the details are not repeated here.

[0106] Finally, it should be noted that the various technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0107] The above-mentioned embodiment only expresses one implementation mode of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the attached claims.

Claims

1. A method for testing air tightness of a load compartment, characterized in that: include: Obtain a load compartment model constructed based on multi-physics field simulation and obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure change law curves under variable temperature conditions through simulation tests; Perform a pressurization test and a pressure-maintaining test on the physical load compartment to obtain the measured initial pressure, the measured initial temperature, and the measured pressure, the measured temperature, and the measured pressure drop corresponding to different pressure-maintaining test durations; According to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test duration, the multiple groups of pressure drop fitting curves and the multiple groups of pressure change law curves under the variable temperature conditions are analyzed, and the theoretical pressure drop under the corresponding pressure holding test duration is determined in combination with the Lagrange interpolation method; When the measured pressure drop does not exceed the theoretical pressure drop, the airtightness of the physical load compartment is determined to be normal; otherwise, the airtightness of the physical load compartment is determined to be abnormal.

2. The load compartment air tightness testing method according to claim 1, characterized in that: The pressure drop fitting curve is used to characterize the change pattern of the air pressure in the load compartment model over time; The pressure variation curve under variable temperature conditions is used to characterize the pressure variation of the load compartment model at different temperatures, with the initial pressure used by the pressure drop fitting curve as the corresponding initial value; The measured pressure drop is used to characterize the actual pressure relief speed of the physical load compartment.

3. The load compartment air tightness testing method according to claim 1, characterized in that: Each group of the pressure drop fitting curves meets the pressure holding time requirement of the physical load compartment, and the initial air pressure of each group of the pressure drop fitting curves meets the air pressure requirement of the physical load compartment.

4. The load compartment air tightness testing method according to claim 1, characterized in that: The analyzing the multiple groups of pressure drop fitting curves and the multiple groups of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure under the corresponding pressure holding test time, and the measured temperature includes: Based on the multiple groups of pressure drop fitting curves, a pressure drop comparison table is constructed; wherein the pressure drop comparison table is used to obtain the pressure drop value per unit time of the load compartment model in multiple groups of simulation tests under constant temperature simulation tests with multiple different initial air pressures as the test starting point, and the average unit time change rate of the pressure in the load compartment model in the corresponding group; Based on the measured initial pressure, query the pressure drop comparison table to determine a first group of simulation data corresponding to a group of pressure drop fitting curves adjacent to the measured initial pressure, and a second group of simulation data adjacent to the first group of simulation data; Based on the measured pressure under the corresponding pressure holding test duration, the first group of simulation data and the second group of simulation data are queried to determine the adjacent pressure adjacent to the measured pressure, the similar pressure adjacent to the adjacent pressure, and the corresponding average unit time change rate of the adjacent pressure and the average unit time change rate of the similar pressure, the measured pressure is between the adjacent pressure and the similar pressure.

5. The load compartment air tightness testing method according to claim 4, characterized in that: The method of analyzing the plurality of pressure drop fitting curves and the plurality of pressure change law curves under the variable temperature conditions according to the measured initial pressure, the measured pressure under the corresponding pressure holding test time, and the measured temperature also includes: Based on the multiple groups of pressure change law curves under variable temperature conditions, a table of the influence of temperature on the air pressure in the load compartment model under a closed state is constructed; wherein the table of the influence of temperature on the air pressure in the load compartment model under a closed state is used to obtain the pressure drop value corresponding to each unit temperature change of the load compartment model in each group of tests under the sealing simulation test, taking the multiple initial air pressures in the pressure drop comparison table as the test starting point, and the average temperature change rate of the pressure in the load compartment model in the corresponding group; According to the measured temperature, query the table of the influence of temperature on the air pressure in the load compartment model under the closed state to determine the adjacent temperature and the similar temperature adjacent to the measured temperature; Based on the measured initial pressure, a table of the influence of temperature on the air pressure in the load compartment model under the closed state is queried to determine a first data group corresponding to a set of air pressure change law curves under variable temperature conditions adjacent to the measured initial pressure and an adjacent average temperature change rate; as well as a second data group corresponding to another set of air pressure change law curves under variable temperature conditions adjacent to the first data group and an adjacent average temperature change rate.

6. The load compartment air tightness testing method according to claim 5, characterized in that: The Lagrange interpolation method is combined to determine the theoretical pressure drop corresponding to the pressure holding test time, including: Based on the measured pressure, adjacent pressure, similar pressure, average rate of change of adjacent pressure per unit time, average rate of change of similar pressure per unit time, combined with the Lagrange interpolation method, the pressure drop rate of equivalent pressure is determined; Based on the measured temperature, adjacent temperature, similar temperature, average change rate of adjacent temperature, average change rate of similar temperature, combined with Lagrange interpolation method, the equivalent temperature pressure drop rate is determined; Based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate, the theoretical pressure drop under the corresponding pressure holding test time is determined.

7. The load compartment air tightness testing method according to claim 6, characterized in that: The determining of the theoretical pressure drop corresponding to the pressure holding test duration based on the equivalent pressure drop rate and the equivalent temperature pressure drop rate includes: Equivalent pressure drop rate = ((measured pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average rate of change of adjacent pressure per unit time + ((actual pressure - adjacent pressure) / (adjacent pressure - adjacent pressure)) × average hourly rate of change of adjacent pressure; Equivalent temperature pressure drop rate = ((measured temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature + ((actual temperature - adjacent temperature) / (adjacent temperature - adjacent temperature)) × average change rate of adjacent temperature; Theoretical pressure drop = equivalent pressure drop rate + equivalent temperature pressure drop rate.

8. The load compartment air tightness testing method according to claim 1, characterized in that: The pressurization test on the physical load compartment includes: The physical load compartment is connected to the booster pump through a connecting pipeline, wherein the connecting pipeline is provided with a pressure gauge for testing the inflation pressure and an on-off control valve for controlling the inflation on and off; Start the booster pump to increase the pressure and slowly increase it to the target initial pressure, ensuring that the boosting time does not exceed 5 minutes; After the air pressure in the physical load compartment is stabilized, the on-off control valve is closed to obtain the measured initial pressure value and the measured initial temperature.

9. A load compartment air tightness test device, characterized in that: include: A simulation module is used to obtain a load compartment model constructed based on multi-physics field simulation and to obtain multiple sets of pressure drop fitting curves of the load compartment model under different simulation initial air pressures and multiple sets of corresponding air pressure change law curves under variable temperature conditions through simulation tests; The physical test module is used to perform a pressurization test and a pressure-maintaining test on the physical load compartment to obtain the measured initial pressure, the measured initial temperature, and the measured pressure, the measured temperature, and the measured pressure drop corresponding to different pressure-maintaining test durations; A test analysis module, for analyzing the multiple sets of pressure drop fitting curves and the multiple sets of pressure change law curves under variable temperature conditions according to the measured initial pressure, the measured pressure and the measured temperature under the corresponding pressure holding test time, and combining the Lagrange interpolation method to determine the theoretical pressure drop under the corresponding pressure holding test time; The result judgment module is used to judge that the airtightness of the physical load compartment is normal when the measured pressure drop does not exceed the theoretical pressure drop, otherwise, it is judged that the airtightness of the physical load compartment is abnormal.

10. A load compartment air tightness test system, characterized in that: The load compartment airtightness testing system comprises the method according to any one of claims 1 to 8, for performing an airtightness test on a physical load compartment.

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