Anti-pollution system applied to plume test

Abstract

The application provides a pollution prevention system applied to a plume test, which comprises at least one pollution prevention cold plate and a reflecting plate, and the pollution prevention cold plate and the reflecting plate surround a plume generation area of the plume test, wherein the pollution prevention cold plate comprises a heat sink cold plate and a molecular adsorption layer coated on the surface of the heat sink cold plate by using a seed coating method, the molecular adsorption layer faces the plume generation area, and the molecular adsorption layer is a porous material; and the reflecting plate is arranged at a position opposite to the engine nozzle in the plume test, so as to reflect the engine plume onto the pollution prevention cold plate. Therefore, the pollution level of other areas in the test container can be reduced, so that the plume pollution molecules are prevented from reaching the test piece and the surface of the heat sink, and the pollution control of the plume test is realized.

Description

Technical Field

[0001] This invention relates to the field of spacecraft plume testing technology, and in particular to a contamination prevention system for plume testing. Background Technology

[0002] Spacecraft plume tests are conducted in a vacuum container. Pollutants are inevitably generated during engine ignition. Based on experimental experience, plume pollutants generally include residual engine propellant and oxidizer, and intermediate products from incomplete combustion. Taking a bicomponent engine as an example, the working fluid is N₂O₄ / MMH, both of which are highly toxic and harmful to humans. N₂O₄ has strong oxidizing properties, a melting point of -9.3℃, a boiling point of 22.4℃, and a saturated vapor pressure of 85.9 kPa (25℃). N₂O₄ coexists with NO₂. NO₂ has a melting point of -11℃, a boiling point of 21℃, and a saturated vapor pressure of 101.32 kPa (22℃). With increasing temperature, N₂O₄ decomposes into NO₂; with decreasing temperature, it polymerizes back into N₂O₄. Methylhydrazine has a melting point of -57.2℃, a boiling point of 62℃, and a saturated vapor pressure of 4.8 kPa (20℃). It is highly flammable and can ignite upon contact with any oxidizer (air).

[0003] If pollutants from the plume test deposit on the spacecraft surface, they can affect the spacecraft's performance or even cause it to fail; if they deposit on the surface of the test container, they can cause corrosive chemical reactions, damaging the thermal properties of the test container surface. If the levels exceed the safety limits for hazardous gases, they can pose a hazard to human health. Therefore, there is an urgent need for a contamination prevention system that can be applied to plume tests to reduce the impact of pollutants generated during plume tests on spacecraft, test containers, and personal safety. Summary of the Invention

[0004] To address the aforementioned shortcomings, the present invention aims to provide an anti-contamination system for plume testing, which can reduce the contamination level in other areas within the test container, thereby preventing plume contaminant molecules from reaching the test specimen and heat sink surface, and achieving contamination control in plume testing.

[0005] To achieve the above objectives, the present invention provides an anti-contamination system for plume experiments, comprising at least one anti-contamination cold plate and a reflector plate, wherein the anti-contamination cold plate and the reflector plate surround the plume generation area of ​​the plume experiment, wherein: The anti-pollution cold plate consists of a heat sink cold plate and a molecular adsorption layer coated on the surface of the heat sink cold plate using an impregnation seed crystal method. The molecular adsorption layer faces the plume generation area and is a porous material. The reflector is positioned directly opposite the engine nozzle during the plume test to reflect the engine plume onto the anti-pollution cold plate.

[0006] Furthermore, the heat sink cold plate is a stainless steel expansion plate type.

[0007] Furthermore, the heat sink plate is provided with liquid nitrogen pipelines on the surface opposite to the molecular adsorption layer.

[0008] Furthermore, the molecular adsorption layer is formed by preparing a ZSM-5 transition layer on the surface of the heat sink cold plate after anodizing treatment via an impregnation seeding method and uniformly spraying it with a molecular sieve impregnation coating liquid containing inorganic adhesive.

[0009] Furthermore, the anti-pollution cold plate is detachably installed in the test container at a predetermined position to surround the plume generation area.

[0010] The anti-contamination system for plume testing described in this invention includes at least one anti-contamination cold plate and a reflector plate, which surround the plume generation area of ​​the plume test. The anti-contamination cold plate consists of a heat sink cold plate and a molecular adsorption layer coated on the surface of the heat sink cold plate using an impregnation seed crystal method. The molecular adsorption layer faces the plume generation area and is made of a porous material. The reflector plate is positioned directly opposite the engine nozzle during the plume test to reflect the engine plume onto the anti-contamination cold plate. Thus, this invention utilizes the low-temperature adsorption of the cold plate structure and the non-desorption properties of the porous material to control contaminants in plume testing under vacuum conditions. This reduces the contamination level in other areas within the test container, thereby preventing plume contaminant molecules from reaching the test piece and heat sink surface, achieving contamination control in plume testing. Attached Figure Description

[0011] Figure 1 This is a structural cross-sectional view of the anti-pollution system applied to a plume test according to an embodiment of the present invention; Figure 2 A front view of the anti-fouling cold plate of the anti-fouling system applied to a plume test according to an embodiment of the present invention; Figure 3 A side cross-sectional view of the anti-fouling cold plate of the anti-fouling system applied to a plume test according to an embodiment of the present invention; Figure 4 for Figure 3 A magnified view of part A in the diagram. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0013] It should be noted that references to "an embodiment," "embodiment," "example embodiment," etc., in this specification refer to the described embodiment including specific features, structures, or characteristics, but not every embodiment must include these specific features, structures, or characteristics. Furthermore, such expressions do not refer to the same embodiment. Moreover, when describing specific features, structures, or characteristics in conjunction with embodiments, whether or not explicitly described, it is indicated that incorporating such features, structures, or characteristics into other embodiments is within the knowledge of those skilled in the art.

[0014] Furthermore, certain terms are used in the specification and subsequent claims to refer to specific components or parts. Those skilled in the art will understand that manufacturers may use different names or terms to refer to the same component or part. This specification and subsequent claims do not distinguish components or parts by differences in name, but rather by differences in function. The terms "comprising" and "including" used throughout the specification and subsequent claims are open-ended and should be interpreted as "including but not limited to." Additionally, the term "connection" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connections made through other means.

[0015] Figures 1-4This invention illustrates an anti-contamination system for use in plume tests, provided by an embodiment of the present invention. The system is used to prevent the diffusion of contaminants generated during spacecraft plume tests. It includes at least one anti-contamination cold plate 10 and a reflector 20, which surround the plume-generating area of ​​the plume test. The anti-contamination cold plate 10 consists of a heat sink cold plate 101 and a molecular adsorption layer 102 coated on the surface of the heat sink cold plate 101 using an impregnation seeding method. The molecular adsorption layer 102 faces the plume-generating area and is made of a porous material. The reflector 20 is positioned directly opposite the engine nozzle 32 during the plume test to reflect the engine plume onto the anti-contamination cold plate 10. During spacecraft plume testing, the engine used in the test ignites inside the vacuum container 41, forming a gas plume 33. This gas plume 33 contains a large amount of pollutants. If not treated, these pollutants will adhere to the test specimen and the heat sink wall 42, thus affecting the test results. Furthermore, it will cause health problems for personnel entering the vacuum container 41 after the test. In this embodiment, at least one anti-pollution cold plate 10 and a reflector 20 are used to surround the plume generation area. Specifically, a semi-enclosed enclosure method is adopted, with the anti-pollution cold plate 10 and the reflector 20 surrounding the bottom and sides of the plume generation area. Then, the molecular adsorption layer 102 on the anti-pollution cold plate 10 adsorbs the plume pollutants, so that a large amount of pollutants are adsorbed on the molecular adsorption layer 102 of the anti-pollution cold plate 10, thereby reducing the pollution level in other areas of the test container and preventing plume pollutant molecules from reaching the test specimen and heat sink surface, thus achieving pollution control of the plume test.

[0016] Specifically, the heat sink plate 101 is a stainless steel expansion plate type; the molecular adsorption layer 102 can be attached to the side of the heat sink plate 101 facing the plume generation area, or the molecular adsorption layer 102 can be attached to both sides of the heat sink plate 101. In this example, it is preferred to provide the molecular adsorption layer 102 on the side of the heat sink plate 101 facing the plume generation area.

[0017] Furthermore, a liquid nitrogen pipeline 103 is provided on the surface of the heat sink 101 on the other side opposite to the molecular adsorption layer 102. Liquid nitrogen is introduced through the liquid nitrogen pipeline 103 to control the temperature of the heat sink 101. In this way, the low-temperature adsorption of the heat sink 101 and the porous material of the molecular adsorption layer 102, which makes the adsorbed substances difficult to desorb, can be used to control pollutants in a plume experiment under vacuum. In specific implementation, the temperature of the heat sink 101 can be controlled through the liquid nitrogen pipeline 103 based on the effect of temperature on pollutants and molecular sieve adsorbents, so as to maximize the molecular sieve adsorption efficiency of the molecular adsorption layer 102.

[0018] In this embodiment, the molecular adsorption layer 102 is formed by uniformly spraying a molecular sieve impregnation coating solution containing inorganic adhesive onto the surface of the heat sink plate 101 after anodizing, by preparing a ZSM-5 transition layer using an impregnation seeding method. Specifically, after anodizing the surface of the heat sink plate 101, a ZSM-5 transition layer is prepared using an impregnation seeding method, and then the final molecular sieve adsorption layer is obtained by impregnation coating with a molecular sieve containing inorganic adhesive, and uniformly sprayed onto the heat sink plate 101, thereby achieving a tight bond between the molecular adsorption layer 102 and the surface of the heat sink plate 101. Furthermore, in order to achieve better adsorption effect of molecular adsorption layer 102, different types of porous materials can be selected to conduct adsorption performance tests on non-metallic materials for spacecraft under vacuum venting. Based on the adsorption performance analysis of adsorbents for different organic molecular pollutants, a suitable adsorbent is selected considering factors such as convenience, practicality, and economy. Then, the adsorption parameters of the selected materials are verified to obtain data reflecting the adsorption performance of the adsorbent. Finally, the porous material is combined with the surface of the heat sink plate 101 to form the molecular adsorption layer.

[0019] The anti-contamination cold plate 10 is detachably installed in the test container at a predetermined position to surround the plume generation area. That is, the anti-contamination cold plate 10 is detachable and replaceable. After the molecular adsorption layer 102 reaches saturation with contaminants, the entire anti-contamination cold plate 10 can be removed and replaced. Alternatively, only the molecular adsorption layer 102 can be removed and replaced from the surface of the heat sink cold plate 101. The removed anti-contamination cold plate 10 or molecular adsorption layer 102 can be vacuum-baked to remove contaminants, enabling reuse and reducing test costs.

[0020] The following describes the plume test method using the aforementioned anti-pollution system, with the specific steps as follows: 1. Cold-rolled steel plate design and processing; 2. Cold impact testing and leak detection of cold-rolled steel plates; 3. Cleaning of cold plates; 4. Arrangement and installation of temperature measuring points on cold plates; 5. Molecular sieve adsorbent is pasted onto the surface of the cold plate; 6. Install the cold plate into the container; 7. Cold plate piping connection and leak detection; 8. Arrangement of water inlet tank inside cold plate container and arrangement of rainproof cloth for cold plate pipes; 9. Evacuate the test container to 10°C. -2 Pa level; 10. Pour liquid nitrogen through the cold plate and heat sink, and start the liquid nitrogen pump; 11. The vacuum degree of the test container is better than 1×10⁻⁶. -2 Pa begins the ignition test; 12. During the ignition process, the cold plate and heat sink are kept in a closed-loop state with liquid nitrogen. 13. After all operating conditions are completed, the test machine shall be shut down; 14. During the test shutdown phase, the vacuum system operates normally, the spacecraft temperature is controlled at 30±5℃, the heat sink begins to warm up, the cold plate switches to liquid supply mode, and liquid nitrogen is continuously supplied. 15. After the heat sink temperature returns to normal, the spacecraft temperature control power is cut off, the vacuum system stops working, and the container begins gas replacement. During this period, the cold plate is kept in a state of liquid nitrogen flow. 16. After gas replacement is completed, the container is repressurized; 17. When the container door is opened, the cold plate stops supplying liquid; 18. After the gas concentration monitoring meets the standard, personnel enter the container and remove the molecular sieve adsorbent (i.e., the molecular adsorption layer) from the heat sink cold plate. At the same time, they wipe the cold plate and its pipes (including the water receiving tank and rainproof cloth) (wipe at least twice, the first time with neutralizing solution and the second time with alcohol). 19. After wiping the cold plate, check the temperature measuring points on the cold plate and the sealing condition of the cold plate pipe connections; 20. A new molecular sieve adsorbent (i.e., a new molecular adsorption layer) is pasted onto the surface of the cold plate in preparation for the next test.

[0021] In summary, the anti-contamination system for plume testing described in this invention includes at least one anti-contamination cold plate and a reflector plate, which surround the plume generation area of ​​the plume test. The anti-contamination cold plate consists of a heat sink cold plate and a molecular adsorption layer coated on the surface of the heat sink cold plate using an impregnation seed crystal method. The molecular adsorption layer faces the plume generation area and is made of a porous material. The reflector plate is positioned directly opposite the engine nozzle during the plume test to reflect the engine plume onto the anti-contamination cold plate. Thus, this invention utilizes the low-temperature adsorption of the cold plate structure and the non-desorption properties of porous materials to control contaminants in plume testing under vacuum conditions. This reduces the contamination level in other areas within the test container, thereby preventing plume contaminant molecules from reaching the test piece and heat sink surface, achieving contamination control in plume testing. It provides a novel contamination protection method for long-life, high-reliability spacecraft and test containers, solving the problem of contamination protection in plume testing.

[0022] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A contamination prevention system for use in plume experiments, characterized in that, It includes at least one anti-fouling cold plate and a reflector plate, said anti-fouling cold plate and said reflector plate surrounding the plume generation area of ​​the plume test, wherein: The anti-pollution cold plate consists of a heat sink cold plate and a molecular adsorption layer coated on the surface of the heat sink cold plate using an impregnation seed crystal method. The molecular adsorption layer faces the plume generation area and is a porous material. The molecular adsorption layer is formed by preparing a ZSM-5 transition layer on the surface of the heat sink cold plate after anodizing treatment via an impregnation seeding method and uniformly spraying it with a molecular sieve impregnation coating liquid containing inorganic adhesive. The reflector is positioned directly opposite the engine nozzle during the plume test to reflect the engine plume onto the anti-pollution cold plate.

2. The anti-contamination system for plume testing according to claim 1, characterized in that, The heat sink and cold plate are stainless steel expansion plates.

3. The anti-contamination system for plume testing according to claim 2, characterized in that, The heat sink plate has a liquid nitrogen pipeline on its surface opposite to the molecular adsorption layer.

4. The anti-contamination system for plume testing according to claim 1, characterized in that, The anti-pollution cold plate is detachably installed in the test container at a predetermined position to surround the plume generation area.

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