Ground thermal test method for space orbit control engine

Abstract

This invention provides a ground hot-fire test method for space orbital control engines, used to assess whether the product can reliably complete on-orbit flight. The method comprises the following steps: Step 1, developing acceptance hot-fire test procedures and operating conditions; Step 2, conducting product acceptance hot-fire tests; Step 3, selecting products for random hot-fire test inspection; Step 4, developing qualification-level life assessment hot-fire test procedures and operating conditions; Step 5, conducting qualification-level life assessment hot-fire tests on randomly selected products; Step 6, evaluating whether the product passes the assessment. The method provided by this invention aims to identify orbital control engine defects in advance through hot-fire test inspections, assess the product's adaptability to flight mission profiles, and ensure the reliable on-orbit operation of long-life space orbital control engines.

Description

Technical Field

[0001] This invention belongs to the field of liquid rocket engine technology, specifically relating to a ground hot-fire testing method for space orbit control engines. More particularly, it relates to a ground hot-fire testing method for long-life space orbit control engines. Background Technology

[0002] For spacecraft such as satellites, the orbit control engine is its heart; its long-term reliable operation is the cornerstone of ensuring successful orbit insertion and on-orbit maneuvering. Ground-based high-altitude simulated hot-fire testing is an effective means of obtaining orbit control engine performance data. However, if the hot-fire testing procedures and conditions are too stringent, it will affect the product's on-orbit reliability margin and pose a risk of failure. Conversely, if the procedures and conditions are too lenient, the product's verification will be insufficient, posing a risk of unexpected on-orbit failure. Therefore, developing a reliable ground-based hot-fire testing method is crucial for the reliable on-orbit operation of long-life space orbit control engines.

[0003] Existing technologies primarily describe high-altitude simulated hot-fire test measurement and control technologies, with limited descriptions of product testing procedures, operating conditions, and evaluation methods. Chinese patent document CN109630322A discloses a test method for a rocket engine thrust chamber, proposing a test method with continuously changing operating conditions. This invention, however, provides a test method that assesses whether a product can be reliably used in orbit for a long period through a combination of acceptance hot-fire tests and randomized hot-fire tests, using different combinations of steady-state constant operating condition procedures. Therefore, the patent document and the method described in this invention belong to different inventive concepts.

[0004] Patent document CN108804813B discloses a method for evaluating the reliability of a space orbit control engine, including the following steps: Step 1, proposing a space orbit control engine design scheme; Step 2, identifying weak points in engine reliability; Step 3, conducting specific reliability tests on the weak points; Step 4, evaluating the reliability of the weak points; Step 5, conducting overall engine reliability verification, integrating engine reliability verification into engine design scheme verification tests and environmental verification tests; Step 6, evaluating engine reliability. However, patent document CN108804813B also fails to assess whether the product can be reliably used in orbit for a long time under steady-state constant operating conditions. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a ground-based hot-fire testing method for space orbital control engines.

[0006] A ground hot-fire test method for a space orbital control engine provided by the present invention includes:

[0007] Step S1: Develop a procedure for product acceptance hot-testing, including the timing of the test under rated operating conditions and off-peak operating conditions.

[0008] Step S2: Conduct product acceptance hot test according to the aforementioned acceptance hot test procedure; wherein, high-modulus test is conducted according to the time required for the rated operating condition and the off-center operating condition.

[0009] Step S3: Select products for hot-run testing;

[0010] Step S4: Develop a qualification-level lifespan hot-running procedure;

[0011] Step S5: Based on the selected sampled hot-test products, conduct hot-test testing for qualification-level lifespan according to the established qualification-level lifespan hot-testing procedure.

[0012] Step S6: Evaluate whether the product passes the assessment.

[0013] Preferably, in step S1, based on the principle that the on-orbit lifespan is acceptable, the cumulative duration of the product hot-test procedure is determined; multiple rated operating condition parameter adjustment procedures are determined, and the minimum procedure required to obtain product performance is determined, and multiple rated operating condition procedures are performed; with the goal of obtaining different operating condition performances of the product and ensuring that the operating conditions have no adverse effects on the product beyond the working time, multiple partial operating condition procedures are determined; wherein, the operating conditions mainly include the combination of thrust and mixture ratio.

[0014] Preferably, in step S2, the test is conducted in a vacuum chamber simulating a vacuum, and a high-mode test is carried out according to the operating conditions in the product acceptance hot test procedure established in step S1 to obtain the throat temperature, specific impulse, and thrust vector parameters of the product under rated operating conditions and other operating conditions.

[0015] Preferably, in step S2, the acceptance hot test conditions are not allowed to be set to conditions with both high mixture ratio and high thrust, and conditions with a mixture ratio greater than 1.68 are not allowed to be set.

[0016] Preferably, in step S3, two products are selected for random hot testing. The rated operating temperature of the product is obtained according to the acceptance hot test in step S2, and the two products with the highest throat temperature are selected as the random testing products.

[0017] Preferably, in step S4, the cumulative time for qualification-level life assessment of the space orbit control engine is determined based on the working time; the longest assessment procedure time for the space orbit control engine is determined based on the duration of a single operation, and the assessment is conducted under rated operating conditions; other assessment conditions and times besides the rated operating conditions are determined based on the product mission profile and margin; and the duration of all other tests is carried out according to the rated operating conditions.

[0018] Preferably, in step S5, the sampled products selected in step S3 are used to conduct a high-altitude hot test for qualification-level life assessment according to step S4; the vacuum degree is less than 2.03 Pa before the first test is started, and the vacuum degree is less than 200 Pa for each of the remaining tests; the specific impulse and throat temperature of the product are obtained during the test.

[0019] Preferably, in step S6, if the following conditions are met simultaneously:

[0020] Condition 1) The delivered product passes the acceptance hot test in step S2, and the specific impulse and thrust vector performance meet the requirements. The product coating is intact and without peeling.

[0021] Condition 2) After the batch of sampled products has undergone the qualification-level life test hot run in step S5, the product structure is intact and it still has the ability to continue working.

[0022] If the product passes the hot-run test, it is considered to have passed the hot-run test; otherwise, the product has failed the hot-run test.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. This invention, through hot test run evaluation, can identify track control engine defects in advance.

[0025] 2. By assessing the product's adaptability to flight mission profiles, this invention can ensure the reliable on-orbit operation of long-life space orbit control engines. Attached Figure Description

[0026] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0027] Figure 1 This is an operational flowchart of the ground hot-fire test and evaluation method for a long-life space orbit control engine according to an embodiment of the present invention.

[0028] Figure 2 This is a schematic diagram of the acceptance hot-testing conditions and procedure duration in an embodiment of the present invention.

[0029] Figure 3 This is a schematic diagram of the hot-running conditions and procedure duration for the qualification-level life assessment in an embodiment of the present invention. Detailed Implementation

[0030] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0031] A ground hot-fire test method for a space orbital control engine, provided by the present invention, is used to assess whether the product can reliably complete on-orbit flight, comprising:

[0032] Step S1: Establish the procedure for product acceptance hot-testing;

[0033] Based on the principle of acceptable on-orbit lifespan, a hot-test procedure for the product with a cumulative duration of 795 seconds was developed. Considering parameter adjustments and thruster stress release during the product testing process, three 15-second rated operating condition parameter adjustment procedures were developed. Considering the minimum procedure required to obtain product performance, eight 50-second rated operating condition procedures were developed. With the goal of obtaining product performance under different operating conditions without any adverse effects on the product beyond the operating time, seven 50-second off-condition procedures were developed. The operating condition range is detailed in [link to relevant documentation]. Figure 2 The operating conditions mainly include the combination of thrust and mixture ratio.

[0034] Step S2: Conduct product acceptance hot-fire test;

[0035] The test is conducted in a vacuum chamber with a simulated vacuum level of less than 200 Pa. The high-mode test is carried out according to the operating conditions in the product acceptance hot test procedure set in step S1 to obtain the throat temperature, specific impulse, and thrust vector parameters of the product's rated operating conditions and other operating conditions. In step S2, the acceptance hot test operating conditions are not allowed to be set to high mixture ratio and high thrust, and the operating conditions with a mixture ratio greater than 1.68 are not allowed to be set.

[0036] Step S3: Select products for hot-run testing;

[0037] Two products were selected for random hot testing. The rated operating temperature of the product was obtained according to step S2. The two products with the highest throat temperature were selected as the random testing products.

[0038] Step S4: Develop a qualification-level lifespan hot-running procedure;

[0039] The cumulative life test time for the long-life space orbit control engine is set at 35,100 seconds, based on 1.5 times the working time; the longest test procedure time for the long-life space orbit control engine is set at 8,100 seconds, based on 1.5 times the duration of a single operation, under rated operating conditions; and other test conditions and times besides the rated operating conditions are set according to the product mission profile and margins. Figure 3 As shown; the remaining tests were conducted under rated operating conditions for a total duration of 30650s; the program layout needs to consider a 15s parameter adjustment program and a 50s performance acquisition program.

[0040] Step S5: Conduct hot-fire testing for qualification-level lifespan assessment on randomly selected products;

[0041] Using the sampled products selected in step S3, conduct high-altitude hot-fire tests for qualification-level life assessment according to step S4; the vacuum degree before the first 15-second test is less than 2.03 Pa, and the vacuum degree of each of the remaining tests is less than 200 Pa; the specific impulse and throat temperature of the product are obtained during the test.

[0042] Step S6: Evaluate whether the product passes the assessment;

[0043] If both conditions are met:

[0044] Condition 1) The delivered product passes the acceptance hot test in step S2, and the specific impulse and thrust vector performance meet the requirements. The product coating is intact and without peeling.

[0045] Condition 2) After the batch of sampled products has undergone the qualification-level life test hot run in step S5, the product structure is intact and it still has the ability to continue working.

[0046] If the product passes the hot-run test, it is considered to have passed the hot-run test; otherwise, the product has failed the hot-run test.

[0047] In step S5, the vacuum level is less than 2.03 Pa before the first test run.

[0048] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0049] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A ground hot-fire test method for a space orbital control engine, characterized in that, include: Step S1: Develop a procedure for product acceptance hot-testing, including the timing of the test under rated operating conditions and off-peak operating conditions. Step S2: Conduct product acceptance hot test according to the aforementioned acceptance hot test procedure; wherein, high-modulus test is conducted according to the time required for the rated operating condition and the off-center operating condition. Step S3: Select products for hot-run testing; Step S4: Develop a qualification-level lifespan hot-running procedure; Step S5: Based on the selected sampled hot-test products, conduct hot-test testing for qualification-level lifespan according to the established qualification-level lifespan hot-testing procedure. Step S6: Evaluate whether the product passes the assessment; In step S1, based on the principle that the on-orbit lifespan is acceptable, the cumulative duration of the product hot-run test procedure is determined; multiple rated operating condition parameter adjustment procedures are determined, and the minimum procedure required to obtain product performance is determined, and multiple rated operating condition procedures are carried out; with the goal of obtaining the product's performance under different operating conditions and ensuring that the operating conditions have no adverse effects on the product beyond the working time, multiple partial operating condition procedures are determined; among them, the operating conditions mainly include the combination of thrust and mixture ratio. In step S4, the cumulative time for qualification-level life assessment of the space orbit control engine is determined based on the working time; the longest assessment procedure time for the space orbit control engine is determined based on the duration of a single working session, and the assessment is conducted under rated operating conditions. In step S4, based on the product task profile and margin, other assessment conditions and times besides the product's rated operating conditions are determined; the test durations for the remaining tests are all carried out according to the rated operating conditions.

2. The ground hot-fire test method for a space orbital control engine according to claim 1, characterized in that, In step S2, a high-mode test is conducted in a vacuum chamber simulating a vacuum, following the operating conditions specified in step S1 for product acceptance hot test, to obtain the throat temperature, specific impulse, and thrust vector parameters of the product under rated operating conditions and other operating conditions.

3. The ground hot-fire test method for a space orbital control engine according to claim 2, characterized in that, In step S2, the acceptance hot test conditions are not allowed to be set to conditions with both high mixture ratio and high thrust, and conditions with a mixture ratio greater than 1.68 are not allowed to be set.

4. The ground hot-fire test method for a space orbital control engine according to claim 1, characterized in that, In step S3, two products are selected for random hot testing. The rated operating temperature of the product is obtained according to the acceptance hot test in step S2. The two products with the highest throat temperature are selected as the random testing products.

5. The ground hot-fire test method for a space orbital control engine according to claim 1, characterized in that, In step S5, the sampled products selected in step S3 are used to conduct a high-altitude hot-fire test for qualification-level life assessment in step S4.

6. The ground hot-fire test method for a space orbital control engine according to claim 5, characterized in that, In step S5, the vacuum degree is less than 2.03 Pa before the first test run, and less than 200 Pa for each of the remaining test runs; the specific impulse and throat temperature of the product are obtained during the test runs.

7. The ground hot-fire test method for a space orbital control engine according to claim 1, characterized in that, In step S6, if the following conditions are met simultaneously: Condition 1) The delivered product passes the acceptance hot test in step S2, and the specific impulse and thrust vector performance meet the requirements. The product coating is intact and without peeling. Condition 2) After the batch of sampled products has undergone the qualification-level life test hot run in step S5, the product structure is intact and it still has the ability to continue working. If the product passes the hot-run test, it is considered to have passed the hot-run test; otherwise, the product has failed the hot-run test.

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