Whole-satellite thermal cycle test method and system

Abstract

The present invention provides a whole-satellite thermal cycle test method and system, relating to the field of spacecraft thermal testing technology. The method comprises the following steps: S1: satellite loading, S2: test state establishment, S3: satellite electrical testing, S4: optical chamber opening, S5: nitrogen replacement, S6: high-temperature baking, S7: normal-pressure thermal cycle test operating conditions, S8: chamber temperature recovery, S9: air replacement, S10: chamber door opening, S11: test withdrawal, and S12: satellite unloading. Compared to traditional whole-satellite thermal vacuum testing, the present invention's whole-satellite normal-pressure thermal cycle test offers significant advantages in terms of liquid nitrogen consumption, personnel requirements, test time, external heat flux equipment, specialized tooling, and operator safety.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft thermal testing, and in particular to a whole-satellite thermal cycle testing method and system. Background Art

[0002] Given the current trend in satellite development, characterized by the parallel development and production of single satellites, small-scale equipment satellites, and large-scale mass-produced satellites, the traditional whole-satellite vacuum thermal testing model, with its long cycles and complex processes, is no longer able to meet the demands of rapid and efficient development for both small-scale equipment satellites and large-scale mass-produced satellites. To adapt to the new mission landscape, optimization of the mass-produced satellite development process is urgently needed. Therefore, based on the successful completion of vacuum thermal testing verification on test satellites, consideration is being given to replacing thermal vacuum testing on some equipment satellites with the shorter, lower-cost atmospheric pressure thermal cycle test, thereby shortening the development process and improving efficiency.

[0003] In recent years, atmospheric pressure thermal testing has been increasingly used by various spacecraft development departments and some civilian spacecraft development units to assess the functionality and performance of large spacecraft structures and satellite components. However, it has not been applied to entire satellites. Furthermore, atmospheric pressure thermal testing research is not systematic, making existing atmospheric pressure thermal cycle testing methods inadequate for guiding the implementation of entire satellite tests. Therefore, the question of how to safely, reliably, and effectively conduct atmospheric pressure thermal cycle testing of entire satellites is a pressing issue. Summary of the Invention

[0004] In view of the defects in the prior art, the purpose of the present invention is to provide a whole-star thermal cycle test method and system.

[0005] A whole-satellite atmospheric pressure thermal cycle test method provided by the present invention is characterized by comprising the following steps:

[0006] S1: Transfer the satellite to the atmospheric pressure thermal cycle test chamber and park it as required to start the test state establishment;

[0007] S2: Adjust the satellite's parking state, check and install the thermal simulation device, pass the satellite's heating wires, temperature measuring wires, and test cables through the normal pressure thermal cycle chamber, and connect them to the corresponding equipment outside the chamber;

[0008] S3: Use wired or wireless methods to test the satellite and check the electromagnetic interference between the electrical systems of the satellite and ground test instruments and test equipment;

[0009] S4: After the test status is established and confirmed by all parties involved in the test, the test is started and the door of the atmospheric pressure thermal cycle chamber is closed;

[0010] S5: Start the gas replacement process in the box to reduce the dew point temperature of the gas in the box to below the minimum test temperature to ensure that there is no condensation risk on the product during the test, and set the working status of the satellite as required;

[0011] S6: When the dew point temperature of the gas in the atmospheric pressure thermal cycle chamber drops below the target temperature, the temperature is raised to the appropriate temperature to bake the satellite to precipitate water vapor inside the chamber and on the satellite;

[0012] S7: After the baking is completed, the satellite enters the normal pressure thermal cycle test condition;

[0013] S8: After all the required thermal cycle tests are completed and the tests are confirmed to be valid, the rewarming stage begins. The product and the ambient temperature in the box reach room temperature and are kept warm for a period of time.

[0014] S9: Replace the nitrogen in the box with clean air until the oxygen content in the box is ≥19%;

[0015] S10: After confirmation by all parties involved in the test, the test is completed and the door of the atmospheric pressure thermal cycle chamber is opened;

[0016] S11: Start the test withdrawal, unlock the heating and temperature measurement cables, remove the light array, and adjust the satellite status;

[0017] S12: Transport the satellite out of the factory and organize the test box and the site as required.

[0018] Preferably, in the above step S2, the insulation resistance and conductivity of all cables are checked, a certain current is applied to an external heat flow simulation device such as an infrared heater or a contact electric heater, and the temperature values ​​of corresponding measuring points in each zone are observed to see whether there are significant changes;

[0019] Preferably, in the above step S7, the ambient temperature in the test chamber is adjusted according to the test requirements, and the heat load of the external heat flow simulation equipment is implemented to make the temperature of the single machine on the satellite reach the specified high / low temperature holding temperature, and maintain this temperature value for a specified time, and then reduce / increase to the specified low / high temperature holding temperature at a predetermined cooling / heating rate, and maintain this temperature value for a specified time to complete a thermal cycle test, repeat the above operation procedure, and complete the specified number of cycle tests as required.

[0020] Preferably, the system is equipped with a gas dew point detector inside the box, and temperature and humidity sensors are installed on the surface of the star and inside the star, for real-time monitoring of the dew point and temperature and humidity inside the box, around the star and inside the star.

[0021] Preferably, in step S7, during the temperature increase and decrease process, the temperature change rate is strictly controlled to ensure that the ambient dew point temperature is always lower than the product temperature.

[0022] Preferably, in step S2, the test product is installed in the test box to ensure that all parts except necessary support points are exposed to the heat transfer medium.

[0023] Preferably, in step S2, in order to improve the external heat flow heating effect under normal pressure environment, the test stars may not be installed in some areas of the multi-layer or the multi-layer buckles may be normally open.

[0024] Preferably, the temperature sensor used to measure the ambient temperature should be placed in the circulating air flow inside the test chamber and should be shielded to prevent the influence of radiant heat transfer.

[0025] The present invention also provides a whole-satellite normal-pressure thermal cycle test system, which adopts the above-mentioned whole-satellite normal-pressure thermal cycle test method.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) Compared with the whole-satellite thermal vacuum test, the whole-satellite atmospheric pressure thermal cycle test of the present invention has a large test space, a simple structure of the external heat flow device, and no external heat flow devices such as infrared heating cages and heat flow meters. The external heat flow equipment is easy and quick to disassemble and assemble, which greatly reduces the manpower consumption in the process of disassembling and assembling the test equipment before and after the test. In addition, the whole-satellite atmospheric pressure thermal cycle test consumes less materials during the test;

[0028] (2) The preparation work before and after the normal-pressure thermal cycle test of the whole satellite in the present invention is simple, avoiding high-risk operations such as assembly and positioning of the absorbing heat sink in the narrow space of the vacuum tank, and effectively reducing the safety risks of personnel, satellites and equipment before and after the test;

[0029] (3) Compared with the traditional whole-satellite thermal vacuum test, the whole-satellite atmospheric pressure thermal cycle test of the present invention has obvious advantages in terms of liquid nitrogen consumption, personnel consumption, test time, external heat flow device, special tooling and operator safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0031] Figure 1 The figure is a flow chart of the whole-star thermal cycle test method under normal pressure of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0033] Example 1

[0034] The present invention provides a method for normal-pressure thermal cycle testing of a whole satellite. Based on the temperature deviation of a normal-pressure thermal cycle test chamber, the temperature of each satellite unit is adjusted during the test through heaters, thermocouples, lamp arrays and single-unit power on / off to achieve the thermal test assessment objectives.

[0035] like Figure 1 The flow chart of the whole-star thermal cycle test method under normal pressure of the present invention is shown. As can be seen from the figure, the whole-star thermal cycle test method of the present invention includes the following steps:

[0036] Step 1: Place the satellite on the transfer vehicle, push the transfer vehicle directly into the normal pressure thermal cycle test chamber and park it in the specified position;

[0037] Step 2: Adjust the levelness of the satellite, check and install the infrared lamp array and heater according to the thermal control design before the test. The test satellite is installed in the test chamber, and all of it is exposed to the heat transfer medium except for the necessary fulcrums. In order to improve the external heat flow heating effect under normal pressure environment, the test satellite is not installed in multiple layers at the heat sink. Install temperature and humidity sensors outside and inside the test star, and wrap aluminum foil around the temperature and humidity sensors to avoid direct infrared light causing the sensor temperature to be too high, resulting in measurement errors. Pass the satellite's heating wire, temperature measuring wire and test cable through the through-holes in the normal pressure thermal cycle chamber, and connect them to the corresponding equipment outside the chamber. Check the insulation resistance and conductivity of all cables, apply a certain current to the external heat flow simulation devices such as infrared heaters and contact electric heaters, and observe whether the temperature values ​​of the corresponding measuring points in each area have obvious changes;

[0038] Step 3: Use wired method to test the satellite and check the electromagnetic interference between the electrical systems of the satellite and ground test instruments and test equipment;

[0039] Step 4: After the test status is established and confirmed by all parties involved in the test, the test is started and the door of the atmospheric pressure thermal cycle chamber is closed;

[0040] Step 5: Start the equipment and replace the air in the box until the dew point temperature inside the box is lower than the minimum test temperature with a certain margin to ensure that there is no condensation risk on the product during the test, and set the working state of the satellite as required. During the operation of the equipment, nitrogen must be added to the box in real time to maintain a slight positive pressure inside the box to prevent moisture from entering the box;

[0041] Step 6: When the dew point temperature of the gas in the atmospheric pressure thermal cycle box drops below -30°C, start heating it to 40°C to bake the satellite and keep it at that temperature for 4 hours.

[0042] Step 7: After the baking is completed, the satellite enters the normal pressure thermal cycle test condition. After the condition starts, the satellite adjusts the temperature of each unit through heaters, thermocouples, lamp arrays and single-unit power on and off based on the temperature deviation of the thermal cycle test chamber. The test condition consists of 4 high and low temperature cycles. During the temperature increase and decrease process, the temperature change rate is strictly controlled to ensure that the ambient dew point temperature is always lower than the product temperature. The system configuration box gas dew point detector and the installed temperature and humidity probes are used throughout the test to monitor the dew point, temperature and humidity in the box, around the satellite and inside the satellite in real time.

[0043] Step 8: After the thermal cycle test is completed and the test is confirmed to be effective, enter the rewarming stage. After the product and the ambient temperature in the box reach room temperature, keep warm for 4 hours;

[0044] Step 9: After the insulation is completed, replace the nitrogen in the box with clean air until the oxygen content in the box is ≥19%;

[0045] Step 10: After confirmation by all parties involved in the test, the test is completed, the box door is opened, and the test withdrawal begins.

[0046] Step 11: Unlock the heating and temperature measurement cables, remove the external heat flow simulation device installed before the test, and adjust the satellite to the transit state;

[0047] Step 12: After the satellite transfer status is established, the satellite is transferred out of the factory, the cables in the box are put away and put in the designated location, and the box is cleaned.

[0048] Example 2

[0049] The present invention provides a whole-satellite normal-pressure thermal cycle test system, which adopts the whole-satellite normal-pressure thermal cycle test method in Example 1.

[0050] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0051] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A whole-star atmospheric pressure thermal cycle test method, characterized in that: The following steps are involved: S1: Transfer the satellite to the atmospheric pressure thermal cycle test chamber and park it as required to start the test state establishment; S2: Adjust the satellite's parking state, check and install the thermal simulation device, pass the satellite's heating wires, temperature measuring wires, and test cables through the normal pressure thermal cycle chamber, and connect them to the corresponding equipment outside the chamber; S3: Use wired or wireless methods to test the satellite and check the electromagnetic interference between the electrical systems of the satellite and ground test instruments and test equipment; S4: After the test status is established and confirmed by all parties involved in the test, the test is started and the door of the atmospheric pressure thermal cycle chamber is closed; S5: Start the gas replacement process in the box to reduce the dew point temperature of the gas in the box to below the minimum test temperature to ensure that there is no condensation risk on the product during the test, and set the working status of the satellite as required; S6: When the dew point temperature of the gas in the atmospheric pressure thermal cycle chamber drops below the target temperature, the temperature is raised to the appropriate temperature to bake the satellite to precipitate water vapor inside the chamber and on the satellite; S7: After the baking is completed, the satellite enters the normal pressure thermal cycle test condition; S8: After all the required thermal cycle tests are completed and the tests are confirmed to be valid, the rewarming stage begins. The product and the ambient temperature in the box reach room temperature and are kept warm for a period of time. S9: Replace the nitrogen in the box with clean air until the oxygen content in the box is ≥19%; S10: After confirmation by all parties involved in the test, the test is completed and the door of the atmospheric pressure thermal cycle chamber is opened; S11: Start the test withdrawal, unlock the heating and temperature measurement cables, remove the light array, and adjust the satellite status; S12: Transport the satellite out of the factory and organize the test box and the site as required.

2. The whole-star normal-pressure thermal cycle test method according to claim 1, characterized in that: In the above step S2, the insulation resistance and conductivity of all cables are checked, a certain current is applied to the external heat flow simulation device of the infrared heater or contact electric heater, and the temperature values ​​of the corresponding measuring points in each zone are observed to see whether there are obvious changes.

3. The whole-star normal pressure thermal cycle test method according to claim 1, characterized in that: In the above step S7, the ambient temperature in the test chamber is adjusted according to the test requirements, and the external heat flow simulation equipment heat load is implemented to make the temperature of the single unit on the satellite reach the specified high / low temperature holding temperature and maintain it at this temperature value for a specified time, and then reduce / increase to the specified low / high temperature holding temperature at a predetermined cooling / heating rate, and maintain it at this temperature value for a specified time to complete a thermal cycle test. Repeat the above operation procedure to complete the specified number of cycle tests as required.

4. The whole-star normal pressure thermal cycle test method according to claim 1, characterized in that: The system is equipped with a gas dew point detector inside the box, and temperature and humidity sensors are installed on the surface and inside the star to monitor the dew point, temperature and humidity inside the box, around the star and inside the star in real time.

5. The whole-star normal pressure thermal cycle test method according to claim 4, characterized in that: In step S7, during the temperature increase and decrease process, the temperature change rate is strictly controlled to ensure that the ambient dew point temperature is always lower than the product temperature.

6. The whole-star normal pressure thermal cycle test method according to claim 1, characterized in that: In step S2, the test product is installed in the test chamber to ensure that all parts except the necessary support points are exposed to the heat transfer medium.

7. The whole-star normal pressure thermal cycle test method according to claim 1, characterized in that: In step S2, in order to improve the external heat flow heating effect under normal pressure environment, some areas of the test star may not be equipped with stars or the multi-layer buckles may be kept open.

8. The whole-star normal pressure thermal cycle test method according to claim 4, characterized in that: The temperature sensor used to measure the ambient temperature should be placed in the circulating air flow inside the test chamber and should be shielded to prevent the influence of radiation heat transfer.

9. A whole-satellite atmospheric pressure thermal cycle test system, characterized in that: The whole-star normal-pressure thermal cycle test method according to any one of claims 1 to 8 is adopted.

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