Propellant safe service life evaluation method based on characteristic parameters

Abstract

The invention provides a propellant safe service life evaluation method based on characteristic parameters. According to the method, the content of an effective stabilizer and the burning rate serve as the characteristic parameters; comprising the steps of 1, measuring original data of characteristic parameters; 2, carrying out a constant-temperature accelerated aging test; 3, testing and arranging a detection time point; 4, predicting and arranging a detection time point; 5, testing and recording data; step 6, truncating; step 7, establishing a characteristic parameter-time curve; 8, estimating the service life by taking the content of the effective stabilizer as a characteristic parameter; and 9, estimating the service life by taking the burning rate as a characteristic parameter. According to the method, the evaluated service life is more accurate, the propellant can meet the requirement for safe use in the whole life cycle, and the purposes that the propellant can be safely stored, and the service life of the propellant can be guaranteed are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of propellants, relates to propellant performance evaluation, and specifically to a method for evaluating the safe service life of a propellant based on characteristic parameters. Background Art

[0002] Propellant is the power source of solid rocket engines. During the long-term storage of solid rocket engines, the performance of propellant charges will change with the external environment and time. The degradation of propellant performance is crucial to whether solid rocket engines can be safely stored and used normally during their service life. The life of propellant can be divided into storage life and service life. During the storage process, some performance parameters of the propellant change over time. When these changes exceed a certain range, the propellant cannot be stored and used normally. The propellant life is the time that can ensure the safe storage and reliable use of the propellant, which can be divided into safe storage life and service life. The safe storage life of the propellant is the time that the propellant can be safely stored without danger under normal storage conditions. The service life refers to the time that the propellant can still complete the specified use function under storage conditions. They are both important indicators for the safe storage and normal use of propellants.

[0003] Different components and different contents of each component in the propellant formula play a critical role in the performance of the formula, so the performance of each propellant formula varies significantly. During the long storage of the engine, the performance of the charge varies greatly with the changes in temperature, humidity, vibration, sedimentation, etc. in the environment. Among the propellant products currently in service, there is a situation where the propellant is not completely burned during long storage, resulting in the engine's initial speed not being reached, affecting the formation of subsequent thrust, and the projectile cannot be launched normally. In severe cases, there is a danger of burning or detonating nearby when the projectile cannot be launched normally. Although the propellant can be stored normally and safely, it can no longer be used safely. For some propellant products, during the routine performance test during storage, the physical and chemical properties, combustion performance, energy performance, mechanical properties, sensitivity and safety performance and other aspects of performance may be within the normal range, but the stability and stability have problems and show a constantly changing dangerous trend. The propellant product cannot continue to be stored safely. Therefore, when ensuring the safe use of the propellant charge, it is necessary to comprehensively consider the requirements of safe and stable storage and normal use of various performances, and to fully meet the needs of weapons and equipment, so it is necessary to take into account safety and use to conduct a safe service life assessment. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for evaluating the safe service life of a propellant based on characteristic parameters, so as to solve the technical problem that the accuracy of the safe service life evaluation method in the prior art needs to be further improved.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0006] The invention discloses a method for evaluating the safe service life of a propellant based on characteristic parameters, wherein the method uses effective stabilizer content and burning rate as characteristic parameters.

[0007] The method comprises the following steps:

[0008] Step 1: Measure the original data of characteristic parameters:

[0009] Firstly, the effective stabilizer content and burning rate of the propellant are measured to obtain the original effective stabilizer content data and the original burning rate data.

[0010] Step 2: Conduct a constant temperature accelerated aging test:

[0011] Select at least four constant temperature points according to the type of propellant to carry out the constant temperature accelerated aging test.

[0012] Step 3: Arrange the test time points:

[0013] 75℃ was selected from the four constant temperature points for constant temperature accelerated test pre-test. Multiple testing time points were arranged according to the change of effective stabilizer content. Effective stabilizer content and burning rate were measured at each testing time point.

[0014] Step 4: Schedule the test time:

[0015] The remaining three constant temperature points among the four constant temperature points are scheduled to have detection time points, and the distribution intervals of the scheduled detection time points are the same as the distribution intervals of the multiple detection time points obtained in step three; the effective stabilizer content and the burning rate are measured at each detection time point.

[0016] Step 5: Test and record data:

[0017] In the constant temperature accelerated aging test at each temperature point, the sampling time of each detection time point is recorded, and the measurement data of the effective stabilizer content and the burning rate are recorded.

[0018] Step 6, truncation:

[0019] The truncation method of the constant temperature accelerated aging test process of the effective stabilizer content adopts constant truncation, and the critical point of truncation is 50% of the effective stabilizer content.

[0020] When the burning rate is lower than the unacceptable value, the truncation method of the constant temperature accelerated aging test process of the burning rate adopts constant truncation, and the critical point of truncation is the unacceptable value.

[0021] When the burning rate has not reached an unacceptable value but the effective stabilizer content has reached the critical point first, the truncation method of the constant temperature accelerated aging test process of the synchronous effective stabilizer content is timed truncation.

[0022] Step 7: Establish characteristic parameter-time curve:

[0023] The effective stabilizer content-time curve and burning rate-time curve were established at four constant temperature points respectively.

[0024] Step 8: Lifespan estimation with effective stabilizer content as characteristic parameter:

[0025] According to the effective stabilizer content-time curve obtained in step seven, the safe period of the propellant at different temperatures, the safe storage life of the propellant at room temperature and the aging decomposition temperature coefficient of the propellant are calculated.

[0026] Step 9: Life estimation with burning rate as characteristic parameter:

[0027] According to the burning rate-time curve obtained in step 7, the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature and the burning rate drop temperature coefficient of the propellant are calculated, and the burning rate is noted as the characteristic parameter.

[0028] The present invention also has the following technical features:

[0029] In step 2, the temperature interval between two adjacent temperature points among the four constant temperature points is 10°C.

[0030] In step three, the setting interval of the multiple detection time points is from the original effective stabilizer content to the effective stabilizer content being less than or equal to 50%.

[0031] In step three, the multiple detection time points are six to seven detection time points.

[0032] In step eight, the calculation method of the safety period of the propellant at different temperatures is as follows: take the effective stabilizer content of 50% as the critical point of failure criterion of the safe storage life of the propellant, draw a parallel line through this point as the horizontal axis, and intersect with the effective stabilizer degradation curve at different temperatures to obtain the time corresponding to each intersection, which is the safety period τ of the propellant at different temperatures. i .

[0033] In step 8, the safe storage life of the propellant at room temperature is calculated as follows:

[0034]

[0035] Where:

[0036] τ 30The safe storage life of the propellant at 30°C;

[0037] A and B are coefficients.

[0038] In step eight, the calculation method of the aging decomposition temperature coefficient of the propellant is:

[0039]

[0040] Where:

[0041] γ 10 is the aging decomposition temperature coefficient of the propellant, that is, the rate of change of decomposition rate for every 10°C increase or decrease in temperature;

[0042] B is the coefficient.

[0043] In step nine, the calculation method of the burning rate failure period of the propellant at different temperatures is:

[0044] Obtain the critical point of propellant burning rate failure. Draw a parallel line with the horizontal axis on the burning rate-time curve obtained in step 7, and intersect it with the burning rate-time curve at different temperatures. Calculate the time corresponding to each intersection, which is the burning rate failure period of the propellant at different temperatures.

[0045] In step nine, the calculation method for the service life of the propellant at room temperature is:

[0046] Based on the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature is calculated by extrapolation using the Besselot equation or the Arrhenius equation, and it is noted that the characteristic parameter is the burning rate.

[0047] In step nine, the calculation method of the propellant burning rate drop temperature coefficient is:

[0048]

[0049] Where:

[0050] γ′ 10 The burning rate drop temperature coefficient of the propellant, that is, the rate of change of the decomposition rate for every 10°C increase or decrease in temperature;

[0051] B' is the coefficient.

[0052] Compared with the prior art, the present invention has the following technical effects:

[0053] (I) The service life evaluated by the method of the present invention is more accurate, and the propellant can meet the requirements of safe use throughout its entire life cycle, achieving a life span during which the propellant can be safely stored and guaranteed to be used.

[0054] (II) The method of the present invention conducts a constant temperature accelerated aging test on the propellant product, selects two characteristic parameters, namely, effective stabilizer content and burning rate, for detection in the test, and adopts a combination of constant truncation and timed truncation to effectively evaluate the safe service life of the propellant.

[0055] (III) The evaluation method of the present invention selects effective stabilizer content and burning rate as characteristic parameters to characterize stability and combustion performance respectively, adopts a four-temperature level high temperature constant temperature accelerated test as a means to accelerate performance degradation, selects the critical points of effective stabilizer content and burning rate as the criterion for safe use, and then uses the Besselot equation or the Arrhenius equation to extrapolate to room temperature to obtain the safe service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a photo of a new sample.

[0057] Figure 2 This is a photo of the accelerated sample tube.

[0058] Figure 3 These are photos of the test specimens and the safety oven.

[0059] Figure 4 This is the variation curve of effective stabilizer content at 55℃ and 65℃.

[0060] Figure 5 This is the variation curve of effective stabilizer content at 75℃ and 85℃.

[0061] Figure 6 This is the burning rate change curve at 55℃ and 65℃.

[0062] Figure 7 This is the burning rate change curve at 75℃ and 85℃.

[0063] The specific contents of the present invention are further explained in detail below in conjunction with embodiments. DETAILED DESCRIPTION

[0064] It should be noted that all materials and equipment in the present invention, unless otherwise specified, are materials and equipment known in the prior art.

[0065] In accordance with the above technical scheme, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical scheme of this application fall within the protection scope of the present invention.

[0066] Example:

[0067] This embodiment provides a method for evaluating the safe service life of a propellant based on characteristic parameters. The method uses the effective stabilizer content and the burning rate as characteristic parameters.

[0068] The method comprises the following steps:

[0069] Step 1: Measure the original data of characteristic parameters:

[0070] Firstly, the effective stabilizer content and burning rate of the propellant are measured to obtain the original effective stabilizer content data and the original burning rate data.

[0071] Step 2: Conduct a constant temperature accelerated aging test:

[0072] Select at least four constant temperature points according to the type of propellant to carry out the constant temperature accelerated aging test.

[0073] In step 2, the temperature interval between two adjacent temperature points among the four constant temperature points is 10°C.

[0074] Specifically in this step, under the premise of ensuring that the aging mechanism of the propellant at each temperature point is the same, four appropriate constant temperature points are selected for testing, and then regression analysis is performed based on the Besselot equation or the Arrhenius equation, and the service life at room temperature is obtained by extrapolation to room temperature.

[0075] Step 3: Arrange the test time points:

[0076] 75℃ was selected from the four constant temperature points for constant temperature accelerated test pre-test. Multiple testing time points were arranged according to the change of effective stabilizer content. Effective stabilizer content and burning rate were measured at each testing time point.

[0077] In step three, the setting interval of the multiple detection time points is from the original effective stabilizer content to the effective stabilizer content being less than or equal to 50%.

[0078] In step 3, the multiple detection time points are six to seven detection time points, ensuring that the effective stabilizer content at each detection time point is evenly distributed throughout the entire interval.

[0079] In this step, the detection time points are divided into effective stabilizer content detection time points and burning rate detection time points, and the burning rate detection time points are set synchronously with the effective stabilizer content detection time points.

[0080] Step 4: Schedule the test time:

[0081] The remaining three constant temperature points among the four constant temperature points are scheduled to have detection time points, and the distribution intervals of the scheduled detection time points are the same as the distribution intervals of the multiple detection time points obtained in step three; the effective stabilizer content and the burning rate are measured at each detection time point.

[0082] Specifically in this embodiment, when the detection time points at three temperatures of 55°C, 65°C and 85°C are estimated based on the 75°C preliminary test, the effective stabilizer content is calculated as approximately 3 times the amount for every 10°C temperature interval.

[0083] Furthermore, in this step, since a large amount of empirical data shows that the burning rate value change in the propellant constant temperature accelerated test does not have a multiple relationship similar to the effective stabilizer content, and each propellant product has different requirements for the burning rate, there is no unified failure critical point for the burning rate in the propellant constant temperature accelerated test, but the burning rate change range is determined according to the specific requirements of the product or test object. The burning rate detection time point is first set synchronously with the effective stabilizer content detection time point, and then the subsequent detection time point is estimated according to the actual measured burning rate data change degree.

[0084] Step 5: Test and record data:

[0085] In the constant temperature accelerated aging test at each temperature point, the sampling time of each detection time point is recorded, and the measurement data of the effective stabilizer content and the burning rate are recorded.

[0086] Step 6, truncation:

[0087] The truncation method of the constant temperature accelerated aging test process of the effective stabilizer content adopts constant truncation, and the critical point of truncation is 50% of the effective stabilizer content.

[0088] When the burning rate is lower than the unacceptable value, the truncation method of the constant temperature accelerated aging test process of the burning rate adopts constant truncation, and the critical point of truncation is the unacceptable value.

[0089] When the burning rate has not reached an unacceptable value but the effective stabilizer content has reached the critical point first, the truncation method of the constant temperature accelerated aging test process of the synchronous effective stabilizer content is timed truncation.

[0090] Further in step 6, there is a unified failure criterion critical point for the effective stabilizer content of the propellant product or test object, namely 50% effective stabilizer content, so the constant temperature accelerated test of the effective stabilizer content is truncated at a constant of 50% effective stabilizer content. There is no unified failure criterion critical point for the burning rate of the propellant product or test object. If the product or test object has an unacceptable value, the constant temperature accelerated test of the burning rate is truncated to a constant of an unacceptable value. If the product or test object does not have an unacceptable value, it is regularly truncated at the failure criterion critical point of the effective stabilizer content.

[0091] Step 7: Establish characteristic parameter-time curve:

[0092] The effective stabilizer content-time curve and burning rate-time curve were established at four constant temperature points respectively.

[0093] In step 7, when the curve is fitted by the data processing software, the curves of each temperature point should select a unified curve model, and a model with the highest possible correlation coefficient should be selected for fitting. It is recommended to use R 2 The value should not be less than 0.99.

[0094] Step 8: Lifespan estimation with effective stabilizer content as characteristic parameter:

[0095] According to the effective stabilizer content-time curve obtained in step seven, the safe period of the propellant at different temperatures, the safe storage life of the propellant at room temperature and the aging decomposition temperature coefficient of the propellant are calculated.

[0096] In step eight, the calculation method of the safety period of the propellant at different temperatures is as follows: take the effective stabilizer content of 50% as the critical point of failure criterion of the safe storage life of the propellant, draw a parallel line through this point as the horizontal axis, and intersect with the effective stabilizer degradation curve at different temperatures to obtain the time corresponding to each intersection, which is the safety period τ of the propellant at different temperatures. i .

[0097] In step 8, the safe storage life of the propellant at room temperature is calculated as follows:

[0098]

[0099] Where:

[0100] τ 30 The safe storage life of the propellant at 30°C;

[0101] A and B are coefficients.

[0102] In step eight, the calculation method of the aging decomposition temperature coefficient of the propellant is:

[0103]

[0104] Where:

[0105] γ 10 is the aging decomposition temperature coefficient of the propellant, that is, the rate of change of decomposition rate for every 10°C increase or decrease in temperature;

[0106] B is the coefficient.

[0107] Step 9: Life estimation with burning rate as characteristic parameter:

[0108] According to the burning rate-time curve obtained in step 7, the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature and the burning rate drop temperature coefficient of the propellant are calculated, and the burning rate is noted as the characteristic parameter.

[0109] In step nine, the calculation method of the burning rate failure period of the propellant at different temperatures is:

[0110] Obtain the critical point of propellant burning rate failure. Draw a parallel line with the horizontal axis on the burning rate-time curve obtained in step 7, and intersect it with the burning rate-time curve at different temperatures. Calculate the time corresponding to each intersection, which is the burning rate failure period of the propellant at different temperatures.

[0111] In step nine, the calculation method for the service life of the propellant at room temperature is:

[0112] Based on the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature is calculated by extrapolation using the Besselot equation or the Arrhenius equation, and it is noted that the characteristic parameter is the burning rate.

[0113] In step nine, the calculation method of the propellant burning rate drop temperature coefficient is:

[0114]

[0115] Where:

[0116] γ′ 10 The burning rate drop temperature coefficient of the propellant, that is, the rate of change of the decomposition rate for every 10°C increase or decrease in temperature;

[0117] B' is the coefficient.

[0118] The evaluation of the safe service life of the propellant based on the combination of the effective stabilizer content and the burning rate of the propellant of the present invention is based on ensuring safe use first, and the evaluation of the safe storage life of the effective stabilizer content parameter is the primary basis. If the service life with the burning rate as the characteristic parameter is shorter than the safe storage life, then the service life is the safe service life. If the service life with the burning rate as the characteristic parameter is longer than the safe storage life, then the safe storage life is the safe service life, that is, the shortest life for safe use is equivalent to the safe storage life, and the propellant can no longer be guaranteed to be used safely beyond this period.

[0119] Application examples:

[0120] This application example provides a method for evaluating the safe service life of a propellant based on characteristic parameters based on the above-mentioned embodiment. The method uses the effective stabilizer content and the burning rate as characteristic parameters.

[0121] First, propellant selection:

[0122] In this application example, the propellant selected is a known modified double-base GOQ propellant as the test object.

[0123] This application example is an evaluation of the safe service life of modified double-base propellant as a propellant charge. After the modified double-base propellant in this application example is ignited by the flame, it produces high-temperature and high-pressure combustion gas. The combustion gas flows through the nozzle and is accelerated, and the thermal energy is converted into kinetic energy to generate thrust, which pushes the projectile out of the launch tube. The modified double-base propellant in this application example has high energy, small pressure index and temperature sensitivity coefficient, and large density, thus ensuring the requirements of engine working time and total impulse.

[0124] Second, test subjects:

[0125] The test sample is a new propellant burning rate strip with a size of Φ5mm×150mm. The accelerated storage test is divided into 4 accelerated temperature stress levels, 8 test time points are set for each temperature point, 5 samples are put into each test time point, and 160 samples are required. Sample photos are shown in Figure 1 and Figure 2 .

[0126] Third, test items:

[0127] The test items include: effective stabilizer content measurement test, burning rate test, and constant temperature accelerated aging test. The effective stabilizer content measurement test is carried out in accordance with the fixed agent bromination method in Method 210.1 of GJB770B-2005 "Test Methods for Gunpowder". The burning rate test is carried out in accordance with the burning rate target line method in Method 7.6.1 of GJB770B-2005 "Test Methods for Gunpowder". The constant temperature accelerated aging test is carried out in accordance with the thermal accelerated aging method for estimating safe storage life in Method 506.1 of GJB770B-2005 "Test Methods for Gunpowder".

[0128] Fourth, method steps:

[0129] The method comprises the following steps:

[0130] Step 1: Measure the original data of characteristic parameters:

[0131] Step 1 in the embodiment is adopted.

[0132] Step 2: Conduct a constant temperature accelerated aging test:

[0133] Step 2 in the embodiment is adopted. In this application example, four temperature levels of 55°C, 65°C, 75°C and 85°C are selected for accelerated aging test according to the characteristics of the modified double-base GOQ propellant formula.

[0134] Step 3: Arrange the test time points:

[0135] Step 3 in the embodiment is adopted. In this application example, Figure 3 As shown, the sample is placed to ensure that the new burning rate powder rod sample does not contact the oven wall.

[0136] Step 4: Schedule the test time:

[0137] Step 4 in the embodiment is adopted. In this application example, according to the test results at 75°C, it is estimated that the detection time points at 55°C, 65°C, and 85°C are arranged. Similarly, 6-7 detection time points are set at each temperature point, and the effective stabilizer content and the burning rate are measured at each detection time point.

[0138] Step 5: Test and record data:

[0139] Step five in the embodiment is adopted.

[0140] Step 6, truncation:

[0141] Step 6 in the embodiment is adopted. In this application example, the effective stabilizer content tracking monitoring is truncated at a critical point of 50%, that is, the effective stabilizer content is 0.71%. The modified double-base GOQ propellant burning rate in this application example has no failure critical point requirement, so it is truncated at the truncated time of the effective stabilizer content.

[0142] Step 7: Establish characteristic parameter-time curve:

[0143] Step 7 in the embodiment is adopted. In this application example, Origin software is used to draw a graph with effective stabilizer content and burning rate as the ordinate and aging time as the abscissa, and the effective stabilizer content-time curve and burning rate-time curve of the sample at a certain constant temperature are obtained respectively. There are four curves at four temperatures. When performing curve fitting, a unified curve model should be selected for the curves at each temperature point. See Figures 4 to 7 .

[0144] Step 8: Life estimation with effective stabilizer content and burning rate as characteristic parameters:

[0145] Step 8 in the embodiment is adopted. In this application example, the results of calculating the index according to the effective stabilizer content are shown in Table 3 and Table 4.

[0146] Step 9: Life estimation with burning rate as characteristic parameter:

[0147] Step 9 in the embodiment is adopted. The modified double-base GOQ propellant in this application example has no critical point requirement for burning rate failure, and the lower limit of the burning rate technical index requirement of its product is taken as the critical point, and the burning rate degradation temperature coefficient and the safe service life with the burning rate as a parameter at different temperatures are obtained by calculation.

[0148] Fifth, test results:

[0149] In step 5, the test results of measuring the effective stabilizer content are shown in Table 1.

[0150] Table 1 Effective stabilizer content measurement test results

[0151]

[0152]

[0153] In step 5, the burning rate test results are shown in Table 2.

[0154] Table 2 Burning rate test results

[0155]

[0156] Sixth, life expectancy:

[0157] In step 8, the lifespan is estimated with the effective stabilizer content as the characteristic parameter:

[0158] The data in Table 1 are plotted against the aging time using the effective stabilizer content. Figure 4 and Figure 5 , calculate the aging time corresponding to 50% consumption of effective stabilizer at each aging temperature from the curve, that is, the critical point of safe storage life at different aging temperatures, see Table 3.

[0159] Table 3 Critical points of safe storage life at different aging temperatures

[0160]

[0161]

[0162] Substituting the data in Table 3 into the following Besselot equation, the empirical formula of the Besselot equation is obtained after regression as follows:

[0163] T=A+B·log10τ

[0164] T=363.43-17.3880logτ

[0165] R 2 =0.9876

[0166] Extrapolated to 30℃, 25℃, and 20℃, the safe storage life of propellant at different temperatures is shown in Table 4, and the aging decomposition temperature coefficient γ of the propellant is obtained. 10 is 3.70.

[0167] Table 4 Safe storage life at different temperatures

[0168] Storage temperature / ℃ 20 25 30 Safe storage life / year 31 16 8

[0169] In step nine, the lifespan estimation with burning rate as the characteristic parameter is:

[0170] The data in Table 2 are plotted as burning rate versus aging time. Figure 6 and Figure 7From the curve, the aging time corresponding to the lower limit of the burning rate at each aging temperature (product burning rate index requirement) of 27.5 mm / s is obtained, that is, the critical point of the burning rate degradation at different aging temperatures, see Table 5.

[0171] Table 5 Burning rate degradation life critical point at different aging temperatures

[0172] Aging temperature / ℃ 55 65 75 85 Burning rate degradation critical point / d 95 23 4.2 6.1

[0173] The burning rate data after aging at 85°C are generally high, which is a systematic deviation during measurement. It is recommended to eliminate it. Substitute the 55°C, 65°C, and 75°C data in Table 8 into the following Besselot equation. After regression, the empirical formula of the Besselot equation is obtained as follows, with good correlation.

[0174] T=A+B·log10τ

[0175] T = 357.05-14.5400logτ

[0176] R 2 =0.9960

[0177] Extrapolated to 30℃, 25℃, and 20℃, the safe service life of the propellant at different temperatures is shown in Table 6, and the propellant burning rate drop temperature coefficient γ′ is obtained 10 It is 4.87.

[0178] Table 6 Burning rate degradation life at different temperatures

[0179] Storage temperature / ℃ 20 25 30 Safe service life / year 70 31 14

Claims

1. A method for evaluating the safe service life of a propellant based on characteristic parameters, characterized in that: This method uses effective stabilizer content and burning rate as characteristic parameters; The method comprises the following steps: Step 1: Measure the original data of characteristic parameters: Firstly, the effective stabilizer content and burning rate of the propellant are measured to obtain the original effective stabilizer content data and the original burning rate data; Step 2: Conduct a constant temperature accelerated aging test: Select at least four constant temperature points according to the type of propellant for constant temperature accelerated aging test; Step 3: Arrange the test time points: 75℃ was selected from the four constant temperature points for constant temperature accelerated test pre-test. Multiple test time points were arranged according to the change of effective stabilizer content. The effective stabilizer content and burning rate were measured at each test time point. Step 4: Schedule the test time: Predicting and arranging detection time points for the remaining three of the four constant temperature points, the distribution interval of the predicted detection time points being the same as the distribution interval of the multiple detection time points obtained in step 3; measuring the effective stabilizer content and the burning rate at each detection time point; Step 5: Test and record data: In the constant temperature accelerated aging test at each temperature point, record the sampling time at each test time point, and record the effective stabilizer content measurement data and burning rate measurement data; Step 6, truncation: The truncation method of the constant temperature accelerated aging test process of the effective stabilizer content adopts constant truncation, and the critical point of truncation is 50% of the effective stabilizer content; When the burning rate is lower than the unacceptable value, the truncation method of the constant temperature accelerated aging test process of the burning rate adopts constant truncation, and the critical point of truncation is the unacceptable value; When the burning rate has not reached an unacceptable value but the effective stabilizer content has reached the critical point first, the truncation method of the isothermal accelerated aging test process of the synchronous effective stabilizer content is timed truncation; Step 7: Establish characteristic parameter-time curve: Establish effective stabilizer content-time curve and burning rate-time curve at four constant temperature points respectively; Step 8: Lifespan estimation with effective stabilizer content as characteristic parameter: According to the effective stabilizer content-time curve obtained in step 7, the safety period of the propellant at different temperatures, the safe storage life of the propellant at room temperature, and the aging decomposition temperature coefficient of the propellant are calculated; Step 9: Life estimation with burning rate as characteristic parameter: According to the burning rate-time curve obtained in step 7, the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature and the burning rate drop temperature coefficient of the propellant are calculated, and the burning rate is noted as the characteristic parameter.

2. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step 2, the temperature interval between two adjacent temperature points among the four constant temperature points is 10°C.

3. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step three, the setting interval of the multiple detection time points is from the original effective stabilizer content to the effective stabilizer content being less than or equal to 50%.

4. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step three, the multiple detection time points are six to seven detection time points.

5. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step eight, the calculation method of the safety period of the propellant at different temperatures is as follows: take the effective stabilizer content of 50% as the critical point of failure criterion of the safe storage life of the propellant, draw a parallel line through this point as the horizontal axis, and intersect with the effective stabilizer degradation curve at different temperatures to obtain the time corresponding to each intersection, which is the safety period τ of the propellant at different temperatures. i .

6. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step 8, the safe storage life of the propellant at room temperature is calculated as follows: Where: τ 30 The safe storage life of the propellant at 30°C; A and B are coefficients.

7. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step eight, the calculation method of the aging decomposition temperature coefficient of the propellant is: Where: γ 10 is the aging decomposition temperature coefficient of the propellant, that is, the rate of change of decomposition rate for every 10°C increase or decrease in temperature; B is the coefficient.

8. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step nine, the calculation method of the burning rate failure period of the propellant at different temperatures is: Obtain the critical point of propellant burning rate failure. Draw a parallel line with the horizontal axis on the burning rate-time curve obtained in step 7, and intersect it with the burning rate-time curve at different temperatures. Calculate the time corresponding to each intersection, which is the burning rate failure period of the propellant at different temperatures.

9. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step nine, the calculation method for the service life of the propellant at room temperature is: Based on the burning rate failure period of the propellant at different temperatures, the service life of the propellant at room temperature is calculated by extrapolation using the Besselot equation or the Arrhenius equation, and it is noted that the characteristic parameter is the burning rate.

10. The method for evaluating the safe service life of a propellant based on characteristic parameters according to claim 1, characterized in that: In step nine, the calculation method of the propellant burning rate drop temperature coefficient is: Where: γ′ 10 The burning rate drop temperature coefficient of the propellant, that is, the rate of change of the decomposition rate for every 10°C increase or decrease in temperature; B' is the coefficient.

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