Static pressure-bearing part airworthiness conformity verification method

Abstract

The invention provides a static pressure-bearing part airworthiness conformity verification method. The method comprises the steps that whether a static pressure-bearing part to be subjected to airworthiness conformity verification can be verified through an analysis method or not is judged; if the static pressure-bearing part can be verified through the analysis method, carrying out airworthiness conformity verification on the static pressure-bearing part according to the analysis method; if the static pressure-bearing part cannot be verified through the analysis method, judging whether a structure similar to the static pressure-bearing part exists or not for an overpressure test; if the judgment result is yes, airworthiness conformity verification is carried out on the static pressure-bearing part in a contrastive analysis mode; and if the judgment result is no, airworthiness conformity verification is carried out on the static pressure-bearing part in a pressure test mode. According to the method for verifying the airworthiness conformity of the static pressure-bearing parts, the airworthiness conformity of the static pressure-bearing parts can be verified by selecting a proper mode, and the problems of complex verification process and certain waste caused by the fact that all the static pressure-bearing parts are directly verified by adopting a pressure test mode are avoided.

Description

Technical Field

[0001] The invention relates to the field of airworthiness certification of aircraft engines, and in particular to an airworthiness compliance verification method for static pressure-bearing parts. Background Art

[0002] As modern aircraft engines continue to pursue economic efficiency, high bypass ratio, high thrust, low fuel consumption, low noise and high safety have become the most important features of modern aircraft engines. As the pressure ratio of the engine continues to increase, the gas pressure of the engine parts that bear gas pressure, such as the casing, continues to increase. In addition, there are also a large number of static parts that bear liquid pressure in modern engines, such as fuel lines, lubricating oil lines, etc. Ensuring the safety of such static pressure-bearing parts during the operation of aircraft engines is the most basic requirement for ensuring the safety of aircraft engines.

[0003] Article 33.64 of my country's currently effective civil aviation engine airworthiness regulations (CCAR33-R2) stipulates that static pressure-bearing parts of engines must meet the following strength requirements under pressure loads: Under pressure conditions, no permanent deformation exceeding the use limit will occur after working for one minute, and no leakage that may cause harmful consequences to the engine will occur; under the breaking pressure, no bursting or explosion will occur after working for one minute.

[0004] Since there are a large number of static pressure parts in modern aircraft engines, according to the requirements of the advisory circular, airworthiness verification tests and analysis / calculations need to be carried out to show the airworthiness compliance of a static pressure part with the CCAR33.64 clause of the engine static pressure parts. At present, the airworthiness compliance verification of static pressure parts is mostly carried out by pressure testing, which is complicated and will cause certain waste. Summary of the invention

[0005] The purpose of the present invention is to provide a method for verifying the airworthiness compliance of static pressure-bearing parts, which can improve the technical problems existing in the prior art that the verification process of airworthiness compliance verification of static pressure-bearing parts is complicated and causes certain waste.

[0006] The embodiments of the present invention can be implemented in the following manner:

[0007] A method for verifying the airworthiness compliance of a static pressure-bearing component, the method comprising the following steps:

[0008] Determine whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by analytical methods;

[0009] If the static pressure-bearing parts can be verified by analytical methods, the airworthiness compliance of the static pressure-bearing parts shall be verified according to the analytical methods;

[0010] If the static pressure-bearing parts cannot be verified by analytical methods, determine whether a structure similar to the static pressure-bearing parts has been subjected to pressure tests; if the judgment result is yes, verify the airworthiness compliance of the static pressure-bearing parts by comparative analysis; if the judgment result is no, verify the airworthiness compliance of the static pressure-bearing parts by pressure tests.

[0011] Optionally, the step of determining whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by an analytical method comprises:

[0012] Determine whether the static pressure-bearing part has a structure with stress concentration. If the static pressure-bearing part has a structure with stress concentration, determine that the static pressure-bearing part cannot be verified for airworthiness compliance by an analytical method;

[0013] If the static pressure-bearing part does not have a structure with stress concentration, pressure test data that meets the preset requirements is obtained; if the pressure test data that meets the preset requirements can be obtained, it is determined that the static pressure-bearing part can be verified by the analysis method; if the pressure test data that meets the preset requirements cannot be obtained, it is determined that the static pressure-bearing part cannot be verified for airworthiness compliance by the analysis method.

[0014] Optionally, the step of verifying the airworthiness compliance of static pressure-bearing parts according to the analysis method includes:

[0015] Select the analytical method to be confirmed;

[0016] Confirming the accuracy of the analysis method to be confirmed based on the pressure test data that meets the preset requirements; if the accuracy of the analysis method to be confirmed meets the preset conditions, adopting the analysis method to be confirmed as the analysis method; if the accuracy of the analysis method to be confirmed does not meet the preset conditions, replacing the analysis method to be confirmed;

[0017] The stress of the static pressure-bearing component under the pressure resistance condition and the overpressure condition is analyzed according to the analysis method, and whether the static pressure-bearing component meets the airworthiness clause is determined according to the stress data.

[0018] Optionally, the step of confirming the accuracy of the analysis method to be confirmed based on the pressure test data that meets the preset requirements includes:

[0019] Obtaining a structural model corresponding to the pressure test data;

[0020] Analyzing the structural model using the analysis method to be confirmed and obtaining analysis data;

[0021] Comparing the analysis data with the pressure test data to confirm whether the accuracy of the analysis method to be confirmed meets the preset conditions;

[0022] The preset condition includes: the deviation between the analysis data and the pressure test data is within a range of 20%.

[0023] Optionally, when the static pressure-bearing parts can be verified by an analytical method, the static pressure-bearing parts airworthiness compliance verification method further includes:

[0024] Determine whether the static pressure-bearing part contains a sub-component with a stress concentration structure; if the static pressure-bearing part contains the sub-component, the airworthiness compliance verification is carried out by adopting an analytical method plus a sub-component test; if the static pressure-bearing part does not contain a sub-component with a stress concentration structure, the airworthiness compliance verification is carried out by adopting an analytical method.

[0025] Optionally, the preset requirements include: having a structural model corresponding to the pressure test data, and the pressure test data includes all test type data related to the airworthiness compliance requirements of the static pressure-bearing parts.

[0026] Optionally, the structure similar to the static pressure-bearing part meets the following conditions: having the same load path as the static pressure-bearing part, being similar in geometric structure to the static pressure-bearing part, and being of the same material type as the static pressure-bearing part.

[0027] Optionally, the step of verifying the airworthiness compliance of the static pressure-bearing parts by comparative analysis includes:

[0028] The structure similar to the static pressure-bearing member is used as a comparative structure;

[0029] Obtaining various parameters of the comparison structure when undergoing a pressure test;

[0030] Obtaining relevant parameters of the static pressure-bearing part;

[0031] The pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are calculated according to the various parameters of the comparison structure and the relevant parameters of the static pressure-bearing parts; if the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are both greater than or equal to 1, the static pressure-bearing parts meet the airworthiness provisions; if the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are not both greater than or equal to 1, the airworthiness compliance verification is carried out by means of pressure verification.

[0032] Optionally, the calculation formula of the compressive strength reserve coefficient is as follows:

[0033]

[0034] Among them, σ rig is the maximum stress of the comparative structure under the pressure of the pressure test; σ einge is the maximum stress of the static pressure-bearing part under the pressure resistance; σ 0.2_eingeis the yield strength of the static pressure-bearing part at the pressure-bearing working temperature; σ 0.2_rig is the yield strength of the comparative structure at the pressure test temperature;

[0035] The calculation formula of the overpressure strength reserve coefficient is as follows:

[0036]

[0037] Among them, σ rig is the maximum stress of the comparative structure under the overpressure test pressure; σ einge is the maximum stress of the static pressure-bearing part under overpressure; σ b_einge is the tensile strength of static pressure-bearing parts under overpressure working temperature; σ b_rig is the tensile strength of the comparative structure at the test temperature.

[0038] Optionally, the static pressure-bearing member is a thin-walled cylindrical structure;

[0039] The calculation formula of the compressive strength reserve coefficient is as follows:

[0040]

[0041] Where ΔP rig is the pressure test pressure of the comparative test; ΔP engine is the pressure resistance of the static pressure-bearing part; t rig is the thickness of the comparative structure; t engine is the thickness of the static pressure-bearing member; R rig is the radius of the comparative structure; R engine is the radius of the static pressure-bearing part; σ 0.2_einge is the yield strength of the static pressure-bearing part at the pressure-bearing working temperature; σ 0.2_rig is the yield strength of the comparative structure at the test temperature;

[0042] The calculation formula of the overpressure strength reserve coefficient is as follows:

[0043]

[0044] Where ΔP rig is the overpressure test pressure of the comparative structure; ΔP engine is the overpressure of the static pressure-bearing part; t rig is the thickness of the comparative structure; t engine is the thickness of the static pressure-bearing member; R rig is the radius of the comparative structure; R engine is the radius of the static pressure-bearing part; σ b_einge is the tensile strength of the static pressure-bearing part under overpressure working temperature; σb_rig is the tensile strength of the comparative structure at the test temperature.

[0045] Optionally, the step of verifying the airworthiness compliance of the static pressure-bearing parts by means of a pressure test includes:

[0046] Obtaining the overpressure condition and the pressure resistance condition of the static pressure-bearing part;

[0047] Obtaining geometric parameters, temperature parameters, material process parameters, and important static load parameters of the static pressure-bearing part;

[0048] Determine the pressure and temperature for pressure testing;

[0049] A pressure test is carried out according to the pressure and temperature, and after the pressure test, it is checked whether permanent deformation exceeding the use limit or leakage occurs; if the inspection results are all negative, it is judged that the static pressure-bearing parts meet the airworthiness provisions.

[0050] Optionally, the step of determining the pressure and temperature for performing the pressure test includes:

[0051] Preset pressure and temperature for pressure test;

[0052] Calculate the compressive strength reserve coefficient and overpressure strength reserve coefficient under the preset pressure and temperature;

[0053] If the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are not both greater than or equal to 1, the preset pressure and temperature during the pressure test are increased until the calculated pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are both greater than or equal to 1, and the preset temperature and pressure are used as the temperature and pressure during the pressure test.

[0054] The calculation formula of the compressive strength reserve coefficient is as follows:

[0055]

[0056] Among them, σ rig is the maximum stress of the static pressure-bearing part under the preset pressure; σ einge is the maximum stress of the static pressure-bearing part under the actual working pressure-resistant condition; σ 0.2_einge σ is the yield strength of the material of the static pressure-bearing part at the actual working pressure-resistant working temperature; 0.2_rig is the yield strength of the static pressure-bearing part material at the preset temperature;

[0057] The calculation formula of the overpressure strength reserve coefficient is as follows:

[0058]

[0059] Among them, σrig is the maximum stress of the static pressure-bearing part under the preset pressure; σ einge is the maximum stress of the static pressure-bearing parts under the overpressure condition in actual operation; σ b_einge σ is the tensile strength of the material of the static pressure-bearing parts under the actual working overpressure temperature; b_rig It is the tensile strength of the static pressure-bearing parts material at a preset temperature.

[0060] The beneficial effects of the method for verifying airworthiness compliance of static pressure-bearing parts provided by the embodiment of the present invention include:

[0061] The embodiment of the present invention provides a method for verifying the airworthiness compliance of static pressure-bearing parts, which includes judging whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by an analysis method; if the static pressure-bearing parts can be verified by an analysis method, the static pressure-bearing parts are verified for airworthiness compliance according to the analysis method; if the static pressure-bearing parts cannot be verified by the analysis method, it is judged whether a structure similar to the static pressure-bearing parts has been subjected to a pressure test; if the judgment result is yes, the static pressure-bearing parts are verified for airworthiness compliance by a comparative analysis method; if the judgment result is no, the static pressure-bearing parts are verified for airworthiness compliance by a pressure test. The method for verifying the airworthiness compliance of static pressure-bearing parts can select a suitable method to verify the airworthiness compliance of static pressure-bearing parts, avoiding the problem that the verification process is complicated and certain waste is caused by directly verifying all static pressure-bearing parts by a pressure test. At the same time, when conducting a pressure test, the static pressure-bearing parts need to be tested under overpressure conditions, which is more dangerous. Therefore, some static pressure-bearing parts do not need to be verified by a pressure test, thus avoiding the occurrence of dangerous situations caused by the pressure test process. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0063] Figure 1 A flowchart of a method for verifying airworthiness compliance of a static pressure-bearing component provided according to one aspect of the present invention is shown;

[0064] Figure 2 A flowchart is shown when step S02 is executed in the method for verifying airworthiness compliance of static pressure-bearing parts according to one aspect of the present invention;

[0065] Figure 3 A flowchart is shown when step S04 is executed in the method for verifying airworthiness compliance of static pressure-bearing parts according to one aspect of the present invention;

[0066] Figure 4 A flow chart is shown when step S05 is executed in the method for verifying airworthiness compliance of static pressure-bearing parts according to one aspect of the present invention. DETAILED DESCRIPTION

[0067] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. Note that the aspects described below in conjunction with the accompanying drawings and specific embodiments are only exemplary and should not be construed as limiting the scope of protection of the present invention in any way.

[0068] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", "vertical" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used, rather than indicating or implying that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0069] At the same time, it should be noted that the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0070] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified or limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, an integral connection, or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or the internal communication of two components, etc. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0071] Explanation of the terms that may be mentioned in the description of the present invention:

[0072] Static pressure-bearing parts: refers to stationary parts that bear large gas or liquid pressure loads, or whose design is affected by the gas or liquid pressure they need to contain. Engine static pressure-bearing parts generally include but are not limited to: compressor casing, combustion chamber casing, turbine casing, heat exchanger, bleed air solenoid valve, engine starting system components, fuel system components, lubricating oil system components, and hydraulic system components. All fuel filler caps require special attention.

[0073] Normal Operating Pressure: The maximum pressure difference that may result under most flight conditions, including pressure pulsations (blockage) of valves and nozzles that deviate from their normal operating conditions.

[0074] Maximum Operating Pressure: The maximum pressure difference under the most severe operating conditions (such as forward flight speed, altitude, ambient temperature, speed and OEI (One-Engine-Inoperative) values). This includes all pressure pulsations caused by valves and nozzles under normal operation, such as significant blocking pressure.

[0075] Maximum possible pressure: The maximum pressure difference that may be caused by the most unfavorable combination of operating conditions (such as forward flight speed, altitude, ambient temperature, speed and OEI rating) caused by failure of related components or control systems during use, or various possible combinations of failures. All pressure pulsations of control elements and valves under normal or emergency conditions need to be considered, including significant blocking pressures.

[0076] Pressure conditions: refers to the pressure conditions described in airworthiness clause CCAR33.64(a)(1) and the temperature, important static loads, material processing performance and geometric shape conditions described in airworthiness clause CCAR33.64(b).

[0077] Overpressure conditions: refers to the pressure conditions described in airworthiness clause CCAR33.64(a)(2) and the temperature, significant static loads, material processing properties and geometric conditions described in airworthiness clause CCAR33.64(b).

[0078] Figure 1 This is a flow chart of the method for verifying the airworthiness compliance of static pressure-bearing parts provided in this embodiment. Figure 1 This embodiment provides a method for verifying the airworthiness compliance of static pressure-bearing parts. The method can enable static pressure-bearing parts to be verified for airworthiness in an appropriate manner, thereby avoiding the problem that all static pressure-bearing parts are directly verified by pressure tests, which results in a complicated verification process and certain waste. At the same time, when conducting pressure tests, static pressure-bearing parts need to be tested under overpressure conditions, which is more dangerous. Therefore, some static pressure-bearing parts do not need to be verified by pressure tests, thus avoiding the occurrence of dangerous situations caused by the pressure test process.

[0079] Specifically, the airworthiness compliance verification method for static pressure-bearing parts provided in this embodiment includes the following steps:

[0080] S01: Determine whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by analytical methods.

[0081] It is judged whether the static pressure-bearing parts undergoing airworthiness compliance verification can be verified by the analysis method. If it is judged that the static pressure-bearing parts can be verified by the analysis method (that is, the judgment conclusion is yes), step S02 is executed; if it is judged that the static pressure-bearing parts cannot be verified by the analysis method (that is, the judgment conclusion is no), step S03 is executed.

[0082] Optionally, before executing step S01, a step of judging whether the static pressure-bearing parts need to undergo airworthiness compliance verification may also be included. Specifically, whether the static pressure-bearing parts need to undergo airworthiness compliance verification is judged based on whether the static pressure-bearing parts are subjected to significant pressure, and the significant pressure is confirmed according to the requirements of CCAR33.64. If the static pressure-bearing parts do not undergo significant pressure, there is no need to demonstrate compliance with CCAR33.64, that is, there is no need to undergo airworthiness compliance verification. Conversely, if the static pressure-bearing parts undergo significant pressure, airworthiness compliance verification is required. Obviously, if it is already clearly known whether the static pressure-bearing parts need to undergo airworthiness compliance verification, there is no need to perform this judgment step.

[0083] In this embodiment, step S01 specifically includes:

[0084] S11: Determine whether the static pressure-bearing part has a structure with stress concentration.

[0085] Generally speaking, if a static pressure-bearing part is provided with structures such as holes and bosses, stress concentration will occur at the structure. If the static pressure-bearing part does not have structures such as holes and bosses that will cause stress concentration, it is judged that the static pressure-bearing part cannot be verified for airworthiness through analytical methods; if the static pressure-bearing part has structures such as holes and bosses that will cause stress concentration, it is judged that the static pressure-bearing part meets the basic requirements for airworthiness verification through analytical methods.

[0086] After executing step S11, if it is determined that the static pressure-bearing parts meet the basic requirements for airworthiness verification by analytical methods, step S12 is executed.

[0087] S12: Determine whether pressure test data that meets preset requirements can be obtained.

[0088] If pressure test data that meets the preset requirements can be obtained, airworthiness compliance verification can be carried out through analytical methods; conversely, if pressure test data that meets the preset requirements cannot be obtained, it is judged that the static pressure-bearing parts cannot be verified for airworthiness compliance through analytical methods.

[0089] Optionally, the preset requirements include: having a structural model corresponding to the pressure test data, and the pressure test data includes all test type data related to the airworthiness compliance requirements of static pressure-bearing parts. Specifically, the pressure test data is the data of a certain structure passing through the pressure test process, and the structural model consistent with the geometric characteristics of the structure is the structural model corresponding to the pressure test data. All test type data related to the airworthiness compliance requirements of static pressure-bearing parts, such as the test results of the airworthiness compliance requirements of a static pressure-bearing part under overpressure conditions and withstand pressure conditions, then accordingly, the overpressure test data must include test data under overpressure conditions and test data under withstand pressure conditions.

[0090] Furthermore, in the process of judging whether a static pressure-bearing part has a stress concentration structure, the structure of the static pressure-bearing part can be analyzed. If the static pressure-bearing part has a main part and sub-components, if the sub-components have a stress concentration structure, the airworthiness compliance of the static pressure-bearing part can be verified by analysis plus sub-component testing. If the static pressure-bearing part does not include a sub-component with a stress concentration structure, the airworthiness compliance of the static pressure-bearing part can be verified by an analytical method.

[0091] When the airworthiness compliance of static pressure-bearing parts is verified by analysis plus sub-component testing, if the results of the analysis verification and the results of the sub-component verification meet the requirements of the clause, it means that the static pressure-bearing parts meet the requirements of the clause.

[0092] S02: Verify the airworthiness compliance of static pressure-bearing parts according to the analytical method.

[0093] After step S01, if it is determined that the static pressure-bearing parts can be verified for airworthiness compliance by using an analysis method or an analysis plus sub-component verification method, step S02 is executed. Figure 2 FIG. 2 is a flowchart showing the process of executing step S02 in the method for verifying the airworthiness compliance of static pressure-bearing parts provided in this embodiment. Figure 1 and Figure 2 The specific steps for verifying the airworthiness compliance of static pressure-bearing parts by analytical methods include:

[0094] S21: Select the analysis method to be confirmed.

[0095] Select any one of the currently conventional analysis methods, which may be, for example, a finite element software simulation analysis method or other industry standard analysis methods.

[0096] S22: Determine the accuracy of the analytical method to be confirmed based on the pressure test data that meets the preset requirements.

[0097] If the judgment result is yes, that is, the accuracy of the analysis method to be confirmed meets the preset conditions, then the confirmed analysis method can be used as the analysis method for analyzing static pressure-bearing parts in the future; if the judgment result is no, that is, the accuracy of the analysis method to be confirmed does not meet the preset conditions, then step S21 is re-executed, and another analysis method is selected as the analysis method to be confirmed until the analysis method to be confirmed whose accuracy meets the preset conditions is obtained.

[0098] In this embodiment, the specific process of step S22 includes:

[0099] Obtain a structural model corresponding to the pressure test data; then use the analysis method to be confirmed selected in step S21 to perform data analysis on the structural model and obtain analysis data; compare the analysis data with the pressure test data to determine whether the accuracy of the analysis method to be confirmed meets the preset conditions.

[0100] Specifically, the preset conditions include: the deviation between the analysis data and the pressure test data is within a range of 20%. In other words, if the analysis data and the pressure test data are compared, if the deviation of the analysis data compared with the pressure test data is less than or equal to 20% of the pressure test data, then it is judged that the accuracy of the analysis method to be confirmed meets the preset conditions, and the analysis method to be confirmed can be used to analyze and verify the airworthiness compliance of the static pressure-bearing parts; on the contrary, if the deviation of the analysis data compared with the pressure test data is greater than 20% of the pressure test data, then it is judged that the accuracy of the analysis method to be confirmed does not meet the preset conditions, and the analysis method to be confirmed cannot be used to analyze and verify the airworthiness compliance of the static pressure-bearing parts, and it is necessary to re-execute step S21 to replace other types of analysis methods.

[0101] S23: Analyze the stress of static pressure-bearing parts under pressure resistance conditions and overpressure conditions according to the analysis method, and determine whether the static pressure-bearing parts meet the airworthiness requirements based on the stress data.

[0102] Specifically, the stress of the static pressure-bearing part under the pressure resistance condition and the overpressure condition is analyzed by the analysis method selected in step S22. If the stress data meets the airworthiness clause, it is judged that the static pressure-bearing part meets the airworthiness clause. Furthermore, if the static pressure-bearing part has a sub-component that needs to be pressure tested, that is, the static pressure-bearing part needs to be verified for airworthiness compliance by analysis plus sub-component verification, then the sub-component needs to be pressure tested at this time.

[0103] S03: Determine whether the structure similar to the static pressure-bearing parts has been subjected to pressure test.

[0104] Determine whether a structure similar to the static pressure-bearing part has been pressure tested before. If there is a structure similar to the static pressure-bearing part that has been pressure tested, that is, the judgment result is yes, then the airworthiness compliance of the static pressure-bearing part can be verified by comparative analysis; if there is no structure similar to the static pressure-bearing part that has been pressure tested before, that is, the judgment result is no, then the airworthiness compliance of the static pressure-bearing part can be verified by pressure testing.

[0105] In this embodiment, the structure similar to the static pressure-bearing member needs to meet the following conditions: having the same load path as the static pressure-bearing member, having a similar geometric structure as the static pressure-bearing member, and having the same material type as the static pressure-bearing member.

[0106] It should be noted that in the description of this embodiment, "similar" is similar in a mathematical sense. Specifically, when all corresponding angles are equal and all distances increase or decrease at the same ratio, two figures are called similar. In other words, in this embodiment, the structure similar to the combined structure of the static pressure-bearing member is a structure whose structural outline is consistent with the static pressure-bearing member, but whose size is different.

[0107] S04: Verify the airworthiness compliance of static pressure-bearing parts through comparative analysis.

[0108] Figure 3 FIG. 4 is a flowchart showing the execution of step S04 in the method for verifying the airworthiness compliance of static pressure-bearing parts provided in this embodiment. Figure 1 and Figure 4 In this embodiment, the structure similar to the static pressure-bearing member is referred to as a comparison structure, and step S04 specifically includes:

[0109] S41: Obtain various parameters of the comparison structure during the pressure test.

[0110] Specifically, the parameters of the comparison structure during the pressure test include: pressure data during the test, geometric parameters of the structure, yield strength of the material, etc.

[0111] S42: Obtain relevant parameters of the static pressure-bearing parts.

[0112] Specifically, the relevant parameters of static pressure-bearing parts include: normal working pressure, maximum working pressure, maximum possible pressure, temperature at various pressures, geometric parameters of the structure, and yield strength and tensile strength of the material, etc.

[0113] S43: Calculate the pressure resistance strength reserve coefficient and overpressure strength reserve coefficient based on the parameters of the comparison structure and the relevant parameters of the static pressure-bearing parts. If the calculated pressure resistance strength reserve coefficient and overpressure strength reserve coefficient are both greater than or equal to 1, it means that the static pressure-bearing parts meet the airworthiness provisions.

[0114] If the calculated pressure resistance strength reserve coefficient and overpressure strength reserve coefficient are not both greater than or equal to 1, it means that the results of the comparative analysis cannot indicate compliance with the clause. In this case, the pressure test method is used to indicate that the requirements of the airworthiness clause are met.

[0115] Specifically, the residual strength coefficient can be calculated by the following formula based on the parameters of the comparison structure and the relevant parameters of the static pressure-bearing parts:

[0116] The calculation formula of compressive strength reserve coefficient is as follows:

[0117]

[0118] Among them, σ rigis the maximum stress of the comparison structure under the pressure test pressure; σ einge is the maximum stress of the static pressure-bearing part under the pressure resistance; σ 0.2_einge is the yield strength of static pressure-bearing parts at the pressure-bearing working temperature; 0.2_rig To compare the yield strength of the structure at the pressure test temperature. It should be noted that the "pressure working condition" mentioned here refers to the actual working condition.

[0119] For the strength reserve coefficient of static pressure-bearing parts of thin-walled cylindrical structures under pressure resistance conditions, the following formula can be used for analogy analysis and calculation:

[0120]

[0121] Among them, ΔP rig is the pressure test pressure of the comparative test; ΔP engine is the pressure resistance of static pressure-bearing parts; t rig is the thickness of the comparison structure; t engine is the thickness of the static pressure-bearing part; R rig is the radius of the comparison structure; R engine is the radius of the static pressure-bearing part; σ 0.2_einge is the yield strength of static pressure-bearing parts at the pressure-bearing working temperature; 0.2_rig To compare the yield strength of the structure at the test temperature.

[0122] The calculation formula of overpressure strength reserve coefficient is as follows:

[0123]

[0124] Among them, σ rig is the maximum stress of the comparison structure under the overpressure test pressure; σ einge is the maximum stress of the static pressure-bearing part under overpressure; σ b_einge is the tensile strength of static pressure-bearing parts under overpressure working temperature; σ b_rig To compare the tensile strength of the structure at the test temperature.

[0125] For the strength reserve coefficient of static pressure-bearing parts of thin-walled cylindrical structures under pressure resistance conditions, the following formula can be used for analogy analysis and calculation:

[0126]

[0127] Where ΔP rig is the overpressure test pressure of the comparison structure; ΔP engine is the overpressure of the static pressure-bearing parts; t rig is the thickness of the comparison structure; t engine is the thickness of the static pressure-bearing part; R rig is the radius of the comparison structure; Rengine is the radius of the static pressure-bearing part; σ b_einge is the tensile strength of static pressure-bearing parts under overpressure working temperature; σ b_rig To compare the tensile strength of the structure at the test temperature.

[0128] S05: Verify the airworthiness compliance of the static pressure-bearing parts by means of pressure test.

[0129] Figure 4 FIG. 1 is a flowchart showing the execution of step S05 in the method for verifying the airworthiness compliance of static pressure-bearing parts provided in this embodiment. Figure 1 and Figure 4 In this embodiment, the specific steps of verifying the airworthiness compliance of static pressure-bearing parts by means of pressure testing include:

[0130] S51: Obtain the overpressure condition and pressure resistance condition of the static pressure-bearing parts.

[0131] Determine the selected working conditions of normal working pressure, maximum working pressure and maximum possible pressure, as well as the temperature and pressure under the selected working conditions, and then obtain the overpressure condition and pressure resistance condition of the static pressure-bearing part according to the above parameters and requirements of the clauses.

[0132] S52: Obtain geometric parameters, temperature parameters, material process parameters, and important static load parameters of static pressure-bearing parts.

[0133] S53: Determine the pressure and temperature for the pressure test.

[0134] First, the pressure and temperature values ​​during the pressure test are preset. Then, the pressure resistance strength reserve coefficient and the overpressure strength reserve coefficient are calculated at the preset pressure and temperature. If the calculated pressure resistance strength reserve coefficient and the overpressure strength reserve coefficient are not both greater than or equal to 1, the temperature and pressure for the pressure test are reset, and the reset temperature and pressure values ​​are greater than the last reset values, that is, the preset pressure and temperature during the pressure test are increased, and the pressure resistance strength reserve coefficient and the overpressure strength reserve coefficient are calculated again, and the above steps are repeated until the calculated pressure resistance strength reserve coefficient and the overpressure strength reserve coefficient are both greater than or equal to 1. At this time, the preset temperature and pressure can be used as the pressure and pressure used when executing step S54. In other words, in this embodiment, the pressure and temperature determined in step S53 are the temperature and pressure when the calculated pressure resistance strength reserve coefficient and the overpressure strength reserve coefficient are both greater than or equal to 1.

[0135] Furthermore, the calculation formula of the compressive strength reserve coefficient is as follows:

[0136] The calculation formula of compressive strength reserve coefficient is as follows:

[0137]

[0138] Among them, σ rig is the maximum stress of the static pressure-bearing part under the preset pressure in the test; σ einge is the maximum stress of static pressure-bearing parts under the actual working pressure condition; 0.2_einge σ is the yield strength of the material of the static pressure-bearing part at the actual working pressure-resistant working temperature; 0.2_rig It is the yield strength of the static pressure-bearing part material at the preset temperature of the test.

[0139] The calculation formula of overpressure strength reserve coefficient is as follows:

[0140]

[0141] Among them, σ rig is the maximum stress of the static pressure-bearing part under the preset pressure in the test; σ einge is the maximum stress of the static pressure-bearing parts under the overpressure condition in actual operation; σ b_einge σ is the tensile strength of the material of the static pressure-bearing parts under the actual working overpressure temperature; b_rig It is the tensile strength of the static pressure-bearing parts material at the preset test temperature.

[0142] S54: Perform a pressure test according to the pressure and temperature determined in step S53, and detect whether permanent deformation exceeding the use limit or leakage occurs after the pressure test. If the inspection result is no, it is determined that the static pressure-bearing part meets the airworthiness requirements.

[0143] The static pressure-bearing parts airworthiness compliance verification method provided by the embodiment of the present invention can effectively determine which method is more appropriate for a static pressure-bearing part to demonstrate its compliance with the CCAR33.64 clause, avoiding the use of pressure tests for all static pressure-bearing parts for airworthiness compliance verification, thereby effectively reducing the airworthiness compliance verification cost of static pressure-bearing parts in aircraft engines. Moreover, when conducting pressure tests, especially when conducting pressure tests on static pressure-bearing parts under overpressure conditions, explosions may occur due to excessive pressure. The verification method provides a method for demonstrating the compliance of static pressure-bearing parts with the clause through a pressure test with a similar structure to the static pressure-bearing parts, and the compliance of the static pressure-bearing parts that need to be demonstrated under pressure-resistant overpressure conditions can be demonstrated through the pressure test with a similar structure.

[0144] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technology in the field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for verifying the airworthiness compliance of static pressure-bearing parts. It is characterized in that The airworthiness compliance verification method for static pressure-bearing parts comprises the following steps: Determine whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by analytical methods; If the static pressure-bearing parts can be verified by analytical methods, the airworthiness compliance of the static pressure-bearing parts shall be verified according to the analytical methods; If the static pressure-bearing parts cannot be verified by analytical methods, determine whether a structure similar to the static pressure-bearing parts has been subjected to pressure tests; if the judgment result is yes, verify the airworthiness compliance of the static pressure-bearing parts by comparative analysis; if the judgment result is no, verify the airworthiness compliance of the static pressure-bearing parts by pressure tests.

2. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 1, It is characterized in that The step of judging whether the static pressure-bearing parts to be verified for airworthiness compliance can be verified by the analytical method comprises: Determine whether the static pressure-bearing part has a structure with stress concentration. If the static pressure-bearing part has a structure with stress concentration, determine that the static pressure-bearing part cannot be verified for airworthiness compliance by an analytical method; If the static pressure-bearing part does not have a structure with stress concentration, pressure test data that meets the preset requirements is obtained; if the pressure test data that meets the preset requirements can be obtained, it is determined that the static pressure-bearing part can be verified by the analysis method; if the pressure test data that meets the preset requirements cannot be obtained, it is determined that the static pressure-bearing part cannot be verified for airworthiness compliance by the analysis method.

3. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 2, It is characterized in that The steps of verifying the airworthiness compliance of static pressure-bearing parts according to the analysis method include: Select the analytical method to be confirmed; Confirming the accuracy of the analysis method to be confirmed based on the pressure test data that meets the preset requirements; if the accuracy of the analysis method to be confirmed meets the preset conditions, adopting the analysis method to be confirmed as the analysis method; if the accuracy of the analysis method to be confirmed does not meet the preset conditions, replacing the analysis method to be confirmed; The stress of the static pressure-bearing component under the pressure resistance condition and the overpressure condition is analyzed according to the analysis method, and whether the static pressure-bearing component meets the airworthiness clause is determined according to the stress data.

4. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 3, It is characterized in that The step of confirming the accuracy of the analysis method to be confirmed based on the pressure test data that meets the preset requirements includes: Obtaining a structural model corresponding to the pressure test data; Analyzing the structural model using the analysis method to be confirmed and obtaining analysis data; Comparing the analysis data with the pressure test data to confirm whether the accuracy of the analysis method to be confirmed meets the preset conditions; The preset condition includes: the deviation between the analysis data and the pressure test data is within a range of 20%.

5. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 2, It is characterized in that In the case where the static pressure-bearing parts can be verified by an analytical method, the static pressure-bearing parts airworthiness compliance verification method further includes: Determine whether the static pressure-bearing part contains a sub-component with a stress concentration structure; if the static pressure-bearing part contains the sub-component, the airworthiness compliance verification is carried out by adopting an analytical method plus a sub-component test; if the static pressure-bearing part does not contain a sub-component with a stress concentration structure, the airworthiness compliance verification is carried out by adopting an analytical method.

6. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 2, It is characterized in that The preset requirements include: having a structural model corresponding to the pressure test data, and the pressure test data includes all test type data related to the airworthiness compliance requirements of the static pressure-bearing parts.

7. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 1, It is characterized in that The structure similar to the static pressure-bearing part meets the following conditions: having the same load path as the static pressure-bearing part, having a similar geometric structure as the static pressure-bearing part, and having the same material type as the static pressure-bearing part.

8. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 1, It is characterized in that The steps of verifying the airworthiness compliance of the static pressure-bearing parts by comparative analysis include: The structure similar to the static pressure-bearing member is used as a comparative structure; Obtaining various parameters of the comparison structure when undergoing a pressure test; Obtaining relevant parameters of the static pressure-bearing part; The pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are calculated according to the various parameters of the comparison structure and the relevant parameters of the static pressure-bearing parts; if the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are both greater than or equal to 1, the static pressure-bearing parts meet the airworthiness provisions; if the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are not both greater than or equal to 1, the airworthiness compliance verification is carried out by means of pressure verification.

9. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 8, It is characterized in that The calculation formula of the compressive strength reserve coefficient is as follows: Among them, σ rig is the maximum stress of the comparative structure under the pressure of the pressure test; σ einge is the maximum stress of the static pressure-bearing part under the pressure resistance; σ 0.2_einge is the yield strength of the static pressure-bearing part at the pressure-bearing working temperature; σ 0.2_rig is the yield strength of the comparative structure at the pressure test temperature; The calculation formula of the overpressure strength reserve coefficient is as follows: Among them, σ rig is the maximum stress of the comparative structure under the overpressure test pressure; σ einge is the maximum stress of the static pressure-bearing part under overpressure; σ b_einge is the tensile strength of static pressure-bearing parts under overpressure working temperature; σ b_rig is the tensile strength of the comparative structure at the test temperature.

10. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 8, It is characterized in that The static pressure-bearing member is a thin-walled cylindrical structure; The calculation formula of the compressive strength reserve coefficient is as follows: Where ΔP rig is the pressure test pressure of the comparative test; ΔP engine is the pressure resistance of the static pressure-bearing part; t rig is the thickness of the comparative structure; t engine is the thickness of the static pressure-bearing member; R rig is the radius of the contrast structure; R engine is the radius of the static pressure-bearing part; σ 0.2_einge is the yield strength of the static pressure-bearing part at the pressure-bearing working temperature; σ 0.2_rig is the yield strength of the comparative structure at the test temperature; The calculation formula of the overpressure strength reserve coefficient is as follows: Where ΔP rig is the overpressure test pressure of the comparative structure; ΔP engine is the overpressure of the static pressure-bearing part; t rig is the thickness of the comparative structure; t engine is the thickness of the static pressure-bearing member; R rig is the radius of the contrast structure; R engine is the radius of the static pressure-bearing part; σ b_einge is the tensile strength of the static pressure-bearing part under overpressure working temperature; σ b_rig is the tensile strength of the comparative structure at the test temperature.

11. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 1, It is characterized in that The steps of verifying the airworthiness compliance of the static pressure-bearing parts by means of pressure testing include: Obtaining the overpressure condition and the pressure resistance condition of the static pressure-bearing part; Obtaining geometric parameters, temperature parameters, material process parameters, and important static load parameters of the static pressure-bearing part; Determine the pressure and temperature for pressure testing; A pressure test is carried out according to the pressure and temperature, and after the pressure test, it is checked whether permanent deformation exceeding the use limit or leakage occurs; if the inspection results are all negative, it is judged that the static pressure-bearing parts meet the airworthiness provisions.

12. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 11, It is characterized in that The steps to determine the pressure and temperature for pressure testing include: Preset pressure and temperature for pressure test; Calculate the compressive strength reserve coefficient and overpressure strength reserve coefficient under the preset pressure and temperature; If the pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are not both greater than or equal to 1, the preset pressure and temperature during the pressure test are increased until the calculated pressure resistance strength reserve coefficient and the over-pressure strength reserve coefficient are both greater than or equal to 1, and the preset temperature and pressure are used as the temperature and pressure during the pressure test.

13. The method for verifying airworthiness compliance of static pressure-bearing parts according to claim 12, It is characterized in that The calculation formula of the compressive strength reserve coefficient is as follows: Among them, σ rig is the maximum stress of the static pressure-bearing part under the preset pressure; σ einge is the maximum stress of the static pressure-bearing part under the actual working pressure-resistant condition; σ 0.2_einge σ is the yield strength of the material of the static pressure-bearing part at the actual working pressure-resistant working temperature; 0.2_rig is the yield strength of the static pressure-bearing part material at the preset temperature; The calculation formula of the overpressure strength reserve coefficient is as follows: Among them, σ rig is the maximum stress of the static pressure-bearing part under the preset pressure; σ einge is the maximum stress of the static pressure-bearing parts under the overpressure condition in actual operation; σ b_einge σ is the tensile strength of the material of the static pressure-bearing parts under the actual working overpressure temperature; b_rig It is the tensile strength of the static pressure-bearing parts material at a preset temperature.

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