Complete machine acceleration test acceleration factor calculation method based on Arrhenius model

Abstract

The invention provides a complete machine acceleration test acceleration factor calculation method based on an Arrhenius model, and the method comprises the steps: obtaining the actual heating temperature of various components through an ANSYS finite element thermal simulation technology, obtaining the failure rate parameters of the corresponding components, and achieving the precise calculation of an acceleration factor. According to the method, the accuracy of reliability evaluation is remarkably improved, and important technical support is provided for engineering application of long-term working requirements of key electronic complete machines in the aerospace field and the like.

Description

Technical Field

[0001] This invention belongs to the field of safety and reliability technology, specifically relating to a method for calculating the acceleration factor of whole-machine accelerated testing based on the Arrhenius model. Background Technology

[0002] To meet the rapid launch requirements of space launch vehicles, they must possess the capability to operate for extended periods. As a core component of the aerospace field, electronic systems must exhibit high reliability during operation to satisfy the technical requirements of rapid rocket launches. Accelerated testing, as a crucial scientific method for evaluating product reliability, significantly shortens the testing cycle by increasing key stresses in the actual application environment, effectively revealing potential failure modes, and thus comprehensively assessing the product's reliability under extreme environmental conditions. The acceleration factor, as a key parameter connecting the accelerated test life and the actual service life of a product, is an important basis for measuring the conversion between pseudo-life and actual life. While previous engineering research has proposed methods for calculating the acceleration factor of the entire system in non-operating states, no systematic research has yet been conducted on calculating the acceleration factor of the entire system in operating states. Therefore, compared to the fact that all component temperatures are ambient temperatures in non-operating states, this study proposes an accelerated testing acceleration factor calculation method based on the Arrhenius model, comprehensively considering the heating temperature of each type of component in operating states. Summary of the Invention

[0003] The purpose of this invention is to solve the problems existing in the prior art, evaluate the reliability of aerospace products under long-term working conditions, and conduct accelerated tests to assess whether their equivalent working time meets the time requirements, so as to provide a guarantee for the rapid launch of rockets.

[0004] This invention provides a method for calculating the acceleration factor in whole-machine accelerated testing based on the Arrhenius model, and the formula for calculating the acceleration factor of the component Arrhenius model is as follows:

[0005]

[0006] In the formula, E a The activation energy is given by k, where k is the Boltzmann constant (8.617 × 10⁻⁶). -5 ev / K), A Fi Let T be the acceleration factor for the i-th type of component. u T represents the normal operating temperature (K) of the i-th type of component; e To accelerate the operating temperature (K) of the i-th type of component.

[0007] The overall acceleration factor based on the Arrennis model is defined as:

[0008]

[0009] In the formula, A FT λ is the acceleration factor for the entire machine. AT To accelerate the overall failure rate of equipment under stress, λ UT This represents the total failure rate of the equipment during actual use.

[0010] The sum of the component failure rates is the total failure rate, and (2) can be changed to

[0011]

[0012] Defined by the acceleration factor, λ Ai =λ Ui ·A Fi Substituting these values, we can obtain the following formula for calculating the overall acceleration factor:

[0013]

[0014] In the formula, m is the number of component types, and n i λ represents the number of components of type i. These two parameters can be obtained from the overall design manual. Ui Let λ be the failure rate of the i-th type of component under normal environmental stress conditions. Ai To accelerate the failure rate of the i-th component under experimental stress conditions; A Fi is the acceleration factor for the i-th type of component.

[0015] In previous engineering studies, the electronic device was in a non-operating state, with all components at the same temperature and generating no heat themselves. Therefore, the component temperatures were consistent with the ambient temperature, and the component failure rate was the non-operating state failure rate, which could be obtained by referring to GJB / Z 108A-2006 "Reliability Prediction Manual for Electronic Equipment in Non-Operating State". In the operating state, due to the different power consumption of different types of components in the electronic device, their heating temperatures vary. Simply using ambient temperature for acceleration factor calculation will not yield an accurate result. Furthermore, since the failure rate in the operating state differs from that in the non-operating state, the original non-operating state failure rate is no longer applicable.

[0016] Therefore, this invention, considering the operating state of electronic devices and taking into account the heating temperature of each type of component under operating conditions, proposes a method for calculating the acceleration factor in accelerated testing of the entire device under operating conditions based on the Arrhenius model. This method uses ANSYS finite element thermal simulation technology to obtain the actual heating temperature of various components and obtains the corresponding component failure rate parameters according to GJB / Z299C-2006 "Handbook for Reliability Prediction of Electronic Equipment under Operating Conditions," thereby achieving accurate calculation of the acceleration factor. This method significantly improves the accuracy of reliability assessment and provides important technical support for engineering applications in aerospace and other fields that require long-term operation of critical electronic devices.

[0017] In formula (4), Where T ui The operating temperature of the component at room temperature, T ei λ represents the operating temperature of the component under accelerated conditions. Ui This represents the failure rate of a component during operation. Since different types of components have different power consumptions, the Tfailure rate for each type of component is... ui With T ei The temperatures are different. For example, in a normal environment of 25℃, the temperature rise of a certain component in the whole machine is 20℃ under normal operating conditions, and the operating temperature will reach 45℃. When an accelerated test is conducted, with the ambient temperature set to 55℃, the component temperature will reach 75℃. The table below compares the accelerated models of the whole machine in non-operating and operating states:

[0018] Table 1 Comparison of the whole machine acceleration model in non-working and working states

[0019]

[0020] By building a digital prototype model of the entire machine and using ANSYS thermal simulation, the operating temperature of each component under working conditions can be obtained.

[0021] This method calculates the acceleration factor under the working state of the whole machine, which can obtain the equivalent working time of the whole product under a certain acceleration test condition, assess whether the product meets the task time requirements, and provide support for evaluating the reliability of the product under working state.

[0022] The beneficial effects of this invention are as follows:

[0023] The proposed method for calculating the acceleration factor of the whole machine is an improvement over the traditional non-working state method. It calculates the actual heating temperature of various components under working conditions and uses ANSYS finite element thermal simulation technology to accurately obtain the actual heating temperature of various components. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0025] Figure 1 This is a temperature distribution diagram from an ANSYS thermal simulation. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] This embodiment provides a method for calculating the acceleration factor in whole-machine accelerated testing based on the Arrhenius model. The formula for calculating the acceleration factor of the component Arrhenius model is as follows:

[0028]

[0029] In the formula, E a The activation energy is given by k, where k is the Boltzmann constant (8.617 × 10⁻⁶). -5 ev / K), A Fi Let T be the acceleration factor for the i-th type of component. u T represents the normal operating temperature (K) of the i-th type of component; e To accelerate the operating temperature (K) of the i-th type of component.

[0030] The overall acceleration factor based on the Arrennis model is defined as:

[0031]

[0032] In the formula, A FT λ is the acceleration factor for the entire machine. AT To accelerate the overall failure rate of equipment under stress, λ UT This represents the total failure rate of the equipment during actual use.

[0033] The sum of the component failure rates is the total failure rate, and (2) can be changed to

[0034]

[0035] Defined by the acceleration factor, λ Ai =λ Ui ·A Fi Substituting these values, we can obtain the following formula for calculating the overall acceleration factor:

[0036]

[0037] In the formula, m is the number of component types, and n i λ represents the number of components of type i. These two parameters can be obtained from the overall design manual. Ui Let λ be the failure rate of the i-th type of component under normal environmental stress conditions. Ai To accelerate the failure rate of the i-th component under experimental stress conditions; A Fi is the acceleration factor for the i-th type of component.

[0038] In previous engineering studies, the electronic device was in a non-operating state, generating no heat. Therefore, the component temperature remained consistent with the ambient temperature, and the component failure rate was the non-operating state failure rate, which could be obtained by referring to GJB / Z108A-2006, "Handbook for Reliability Prediction of Electronic Equipment in Non-Operating State." In the operating state, due to the different power consumption of different types of components in the electronic device, their heating temperatures vary. Simply using ambient temperature for acceleration factor calculation will not yield accurate results. Furthermore, since the failure rate in the operating state differs from that in the non-operating state, the original non-operating state failure rate is no longer applicable.

[0039] Therefore, this invention, considering the operating state of electronic devices and taking into account the heating temperature of each type of component under operating conditions, proposes a method for calculating the acceleration factor in accelerated testing of the entire device under operating conditions based on the Arrhenius model. This method uses ANSYS finite element thermal simulation technology to obtain the actual heating temperature of various components and obtains the corresponding component failure rate parameters according to GJB / Z299C-2006 "Handbook for Reliability Prediction of Electronic Equipment under Operating Conditions," thereby achieving accurate calculation of the acceleration factor. This method significantly improves the accuracy of reliability assessment and provides important technical support for engineering applications in aerospace and other fields that require long-term operation of critical electronic devices.

[0040] In formula (4), Where T ui The operating temperature of the component at room temperature, T ei λ represents the operating temperature of the component under accelerated conditions. Ui This represents the failure rate of a component during operation. Since different types of components have different power consumptions, the Tfailure rate for each type of component is... ui With T eiThe temperatures are different. For example, in a normal environment of 25℃, the temperature rise of a certain component in the whole machine is 20℃ under normal operating conditions, and the operating temperature will reach 45℃. When an accelerated test is conducted, with the ambient temperature set to 55℃, the component temperature will reach 75℃. The table below compares the accelerated models of the whole machine in non-operating and operating states:

[0041] Table 1 Comparison of the whole machine acceleration model in non-working and working states

[0042]

[0043] By building a digital prototype model of the entire machine and using ANSYS thermal simulation, the operating temperature of each component under working conditions can be obtained.

[0044] This method calculates the acceleration factor under the working state of the whole machine, which can obtain the equivalent working time of the whole product under a certain acceleration test condition, assess whether the product meets the task time requirements, and provide support for evaluating the reliability of the product under working state.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for calculating the acceleration factor in whole-machine acceleration testing based on the Arrhenius model, characterized in that, Under operating conditions, the actual heating temperature of various components is calculated using the following formula: In the formula, A FT λ is the acceleration factor for the entire machine. AT To accelerate the overall failure rate of equipment under stress, λ UT This represents the total failure rate of the equipment during actual use.

2. The method for calculating the acceleration factor of a whole-machine acceleration test based on the Arrhenius model according to claim 1, characterized in that, Based on the fact that the sum of component failure rates equals the total failure rate and is defined by the acceleration factor, the formula for calculating the overall system acceleration factor is as follows: Among them, A FT The acceleration factor is the overall system speedup factor, where m is the number of component types and n is the overall system speedup factor. i Let λ be the number of components of type i. Ui Let A be the failure rate of the i-th type of component under normal environmental stress conditions. Fi is the acceleration factor for the i-th type of component.

3. The method for calculating the acceleration factor of a whole-machine acceleration test based on the Arrhenius model according to claim 2, characterized in that, A digital prototype model of the entire machine was built, and the operating temperature of each component under working conditions was obtained through ANSYS thermal simulation.

4. The method for calculating the acceleration factor of a whole-machine acceleration test based on the Arrhenius model according to claim 3, characterized in that, The number of component types and the number of a certain type of component can be obtained from the overall design manual.

5. The method for calculating the acceleration factor of a whole-machine acceleration test based on the Arrhenius model according to claim 4, characterized in that, Obtain the corresponding component failure rate parameters according to GJB / Z299C-2006 "Reliability Prediction Manual for Operating Conditions of Electronic Equipment".

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