A method and system for evaluating the strength of a locking piece of a rotor connection structure

Abstract

The present invention belongs to the field of aeroengines, and relates to a technique for evaluating the strength of a lock piece in a rotor balancing screw. A method and system for evaluating the strength of a lock piece in a rotor connection structure are disclosed, and the method includes: performing an elastic-plastic analysis on an initial lock piece finite element model constructed, and correcting the initial lock piece finite element model according to the result of the elastic-plastic analysis to obtain a lock piece finite element model; constructing a non-warping finite element model and a warping finite element model of a rotor connection structure through the lock piece finite element model, a screw and a matrix, and obtaining the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the lock piece at the root of the screw pressing in the warping finite element model under working conditions; and evaluating the strength reserve of the lock piece according to the measured tensile properties of the lock piece, the fatigue limit of the lock piece, the results of the elastic-plastic analysis, the stress of the bending part of the positioning claw and the stress of the lock piece at the root of the screw pressing. The present invention can realize accurate evaluation of the risk of the lock piece under working conditions, and provide data guidance for the reasonable design of the lock piece.

Description

Technical Field

[0001] The invention belongs to the field of aeroengines, and relates to a lock plate strength assessment technology in a rotor balancing screw, and in particular to a lock plate strength assessment method and system for a rotor connection structure. Background Art

[0002] At present, the rotors of aircraft engines are generally balanced by a structure of screws and locking plates. The screws are locked by the locking plates to prevent them from loosening. When installing the locking plates, the fixing claws are bent and fit against the edge of the screws, and the positioning claws are bent and fit against the surface of the substrate for locking.

[0003] Since the operating space of the aircraft engine rotor is limited after assembly, the lock plate may be damaged when installing the stop lock plate. In addition, the lock plate is subjected to high mechanical loads, thermal loads, and aerodynamic loads during operation. The working environment is harsh. During the operation of the engine, the lock plate may crack or even break, which has a serious impact on the safety of the engine.

[0004] However, there is currently a lack of effective strength assessment methods for stop lock plates, which has led to an increasingly prominent problem of lock plate failure, posing a serious threat to the safe operation of aircraft engines. Summary of the invention

[0005] In order to solve the technical problem that it is difficult to reduce the hidden dangers of safe operation of aircraft engines due to the lack of an effective strength assessment method for a stop lock plate in the prior art, the present invention discloses a method for assessing the strength of a lock plate of a rotor connection structure, the method comprising the following steps:

[0006] S1, performing an elastic-plastic analysis on the constructed initial locking piece finite element model, and modifying the initial locking piece finite element model according to the elastic-plastic analysis result to obtain a locking piece finite element model;

[0007] S2. Constructing a non-warping finite element model and a warping finite element model of the rotor connection structure through the locking piece finite element model, the screw and the matrix, and obtaining the stress of the bending part of the positioning claw in the non-warping finite element model and the locking piece stress at the root of the screw pressing in the warping finite element model under working conditions;

[0008] S3. Evaluate the strength reserve of the locking piece based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the elastic-plastic analysis results, the stress at the bending part of the positioning claw, and the stress of the locking piece at the root of the screw compression.

[0009] Furthermore, in step S1, an elastic-plastic analysis is performed on the constructed initial locking piece finite element model, and the initial locking piece finite element model is corrected according to the elastic-plastic analysis result to obtain the locking piece finite element model, including:

[0010] S11, constructing an initial lock piece finite element model according to the lock piece structure using the initial material of the lock piece, and setting the lock piece plastic strain threshold according to the elongation of the lock piece material;

[0011] S12, using a finite element method, gradually applying bending loads to the fixing claw and the positioning claw of the initial locking piece finite element model, respectively, to obtain a first bending load corresponding to when the fixing claw is bent to a set angle and a second bending load corresponding to when the positioning claw is bent to a set angle;

[0012] S13, calculating a first plastic strain and a first residual plastic stress at a bending portion of the fixing claw according to the first bending load, and calculating a second plastic strain and a second residual plastic stress at a bending portion of the positioning claw according to the second bending load;

[0013] S14. Evaluate the initial locking piece finite element model according to the first plastic strain at the bending portion, the second plastic strain at the bending portion and the locking piece plastic strain threshold, and modify the locking piece material for constructing the initial locking piece finite element model according to the evaluation result to obtain the locking piece finite element model that meets the locking piece plastic strain threshold.

[0014] Furthermore, in step S14, the initial locking piece finite element model is evaluated according to the first plastic strain of the bending portion, the second plastic strain of the bending portion and the plastic strain threshold of the locking piece, and the locking piece material for constructing the initial locking piece finite element model is modified according to the evaluation result to obtain the locking piece finite element model that meets the locking piece plastic strain threshold, including:

[0015] S141, comparing the first plastic strain of the bending portion and the second plastic strain of the bending portion with a plastic strain threshold, and when both the first plastic strain of the bending portion and the second plastic strain of the bending portion are smaller than the plastic strain threshold of the locking piece, using the initial locking piece finite element model as the locking piece finite element model;

[0016] S142. When any one of the first plastic strain at the bending portion and the second plastic strain at the bending portion is greater than the plastic strain threshold of the locking plate, a new locking plate material having a material elongation greater than that of the initial material of the locking plate is selected to correct the initial locking plate finite element model to obtain a locking plate finite element model that meets the plastic strain threshold of the locking plate.

[0017] Furthermore, in step S11, the plastic strain threshold of the locking plate is 0.5 times the elongation of the locking plate material, and in step S12, the set angle is 90°.

[0018] Further, in step S2, a warped finite element model of the rotor connection structure is constructed by using the locking piece finite element model, the screw and the matrix, including:

[0019] S21. Under the assembly condition, an axial interference is applied to the mating end faces of the locking plate and the screw, and a load in a direction opposite to the bending direction of the positioning claw is gradually applied to the bending position of the positioning claw until the end face of the locking plate is warped;

[0020] S22, unloading the load to obtain the initial warping of the locking piece, calculating the residual plastic stress of the locking piece at the root of the screw compression according to the initial warping of the locking piece, and establishing a warped finite element model including the locking piece finite element model, the screw and the substrate according to the initial warping of the locking piece.

[0021] Further, in step S2, the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the locking piece at the screw compression root in the warping finite element model under working conditions are obtained, including:

[0022] S23. Under working conditions, loading a working load into the warping-free finite element model and loading an axial interference on the mating end faces of the locking plate and the screw to obtain stress at the bending portion of the positioning claw;

[0023] S24. Under working conditions, a working load is loaded into the warped finite element model and an axial interference is loaded on the mating end faces of the locking plate and the screw to obtain the locking plate stress at the root of the screw.

[0024] Further, in step S3, the strength reserve of the locking piece is evaluated based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the elastic-plastic analysis result, the stress of the bending part of the positioning claw and the stress of the locking piece at the root of the screw compression, including:

[0025] S31, calculating the effective stress at the bending part of the positioning claw according to the second residual plastic stress and the stress at the bending part of the positioning claw in the elastic-plastic analysis result;

[0026] S32, calculating the effective stress of the screw compression root locking piece according to the screw compression root locking piece stress and the residual plastic stress of the screw compression root locking piece;

[0027] S33, testing the locking piece to obtain the measured tensile properties of the locking piece, and evaluating the static strength reserve of the locking piece based on the measured tensile properties of the locking piece, the effective stress at the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression;

[0028] S34. Evaluate the dynamic strength reserve of the locking piece according to the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the effective stress of the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression.

[0029] Furthermore, in step S33, the static strength reserve of the locking piece is evaluated based on the measured tensile properties of the locking piece, the effective stress of the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression, including:

[0030] S331, comparing the maximum value of the effective stress at the bending part of the positioning claw and the effective stress of the locking piece at the root of the screw compression with the measured tensile property of the locking piece, if the maximum value is less than or equal to the measured tensile property of the locking piece, it is determined that the static strength reserve of the locking piece meets the design requirements;

[0031] S332: If the maximum value is greater than the actually measured tensile property of the locking piece, it is determined that the static strength reserve of the locking piece does not meet the design requirements.

[0032] Furthermore, in step S34, the dynamic strength reserve of the locking piece is evaluated according to the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the effective stress of the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression, including:

[0033] S341, calculating the allowable vibration stress of the locking piece according to the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the effective stress of the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression;

[0034] S342, testing the locking plate to obtain the locking plate vibration stress, and if the ratio of the locking plate allowable vibration stress to the locking plate vibration stress is greater than a ratio threshold, determining that the locking plate dynamic strength reserve meets the design requirements;

[0035] S343: If the ratio of the allowable vibration stress of the locking plate to the vibration stress of the locking plate is greater than a ratio threshold, it is determined that the dynamic strength reserve of the locking plate does not meet the design requirements.

[0036] An embodiment of the present invention further provides a lock plate strength assessment system for a rotor connection structure, the lock plate strength assessment system comprising a lock plate finite element model correction module, a rotor connection structure finite element model construction module, a stress calculation module and a strength reserve assessment module.

[0037] The locking piece finite element model correction module is used to perform elastic-plastic analysis on the constructed initial locking piece finite element model, and correct the initial locking piece finite element model according to the elastic-plastic analysis result to obtain the locking piece finite element model;

[0038] The rotor connection structure finite element model building module is used to build a non-warping finite element model and a warping finite element model of the rotor connection structure through the locking piece finite element model, the screw and the matrix;

[0039] The stress calculation module is used to obtain the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the locking piece at the root of the screw compression in the warping finite element model under working conditions;

[0040] The strength reserve assessment module is used to assess the strength reserve of the locking plate based on the measured tensile properties of the locking plate, the fatigue limit of the locking plate, the elastic-plastic analysis results, the stress at the bending part of the positioning claw, and the locking plate stress at the root of the screw compression.

[0041] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above-mentioned technical solutions adopted in the embodiments of this specification include at least: the locking plate strength assessment method of the rotor connection structure of the present invention, which assesses the locking plate material, the locking plate static strength reserve and the locking plate dynamic strength reserve in three aspects, can realize accurate assessment of the locking plate risk under working conditions and provide data guidance for the reasonable design of the locking plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 A flow chart of a method for evaluating the strength of a locking piece of a rotor connection structure disclosed in an embodiment of the present invention;

[0044] Figure 2 A flow chart of a method for evaluating the strength of a locking piece disclosed in an embodiment of the present invention;

[0045] Figure 3 It is an architecture diagram of a lock piece strength evaluation system of a rotor connection structure disclosed in an embodiment of the present invention;

[0046] Among them, 301, a lock piece finite element model correction module; 302, a rotor connection structure finite element model construction module; 303, a stress calculation module; 304, a strength reserve assessment module. DETAILED DESCRIPTION

[0047] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0048] The following describes the implementation methods of the present application through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and the features of the embodiments can be combined with each other in the absence of conflict. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0049] The embodiment of the present invention discloses a method for evaluating the strength of a locking piece of a rotor connection structure, see Figure 1 As shown, the method comprises the following steps:

[0050] S1, performing an elastic-plastic analysis on the constructed initial locking piece finite element model, and modifying the initial locking piece finite element model according to the elastic-plastic analysis result to obtain a locking piece finite element model;

[0051] S2. Constructing a non-warping finite element model and a warping finite element model of the rotor connection structure through the locking piece finite element model, the screw and the matrix, and obtaining the stress of the bending part of the positioning claw in the non-warping finite element model under working conditions and the locking plate stress at the root of the screw in the warped finite element model ;

[0052] S3, tensile properties measured based on the cleat , fatigue limit of the locking piece, the elastic-plastic analysis results, the stress of the bending part of the positioning claw and the screw compression root lock plate stress , perform strength reserve assessment on the cleat.

[0053] Furthermore, in step S1, an elastic-plastic analysis is performed on the constructed initial locking piece finite element model, and the initial locking piece finite element model is corrected according to the elastic-plastic analysis result to obtain the locking piece finite element model, including:

[0054] S11, constructing an initial lock piece finite element model according to the lock piece structure using the initial material of the lock piece, and setting the lock piece plastic strain threshold according to the elongation of the lock piece material;

[0055] S12, using a finite element method, gradually applying bending loads to the fixing claw and the positioning claw of the initial locking piece finite element model, respectively, to obtain a first bending load corresponding to when the fixing claw is bent to a set angle and a second bending load corresponding to when the positioning claw is bent to a set angle;

[0056] S13, calculating a first plastic strain of the bending portion of the fixing claw according to the first bending load and the first residual plastic stress , calculate the second plastic strain of the bending part of the positioning claw according to the second bending load and the second residual plastic stress ;

[0057] S14. Evaluate the initial locking piece finite element model according to the first plastic strain at the bending portion, the second plastic strain at the bending portion and the locking piece plastic strain threshold, and modify the locking piece material for constructing the initial locking piece finite element model according to the evaluation result to obtain the locking piece finite element model that meets the locking piece plastic strain threshold.

[0058] Furthermore, in step S14, the initial locking piece finite element model is evaluated according to the first plastic strain of the bending portion, the second plastic strain of the bending portion and the plastic strain threshold of the locking piece, and the locking piece material for constructing the initial locking piece finite element model is modified according to the evaluation result to obtain the locking piece finite element model that meets the locking piece plastic strain threshold, including:

[0059] S141, comparing the first plastic strain of the bending portion and the second plastic strain of the bending portion with a plastic strain threshold, and when both the first plastic strain of the bending portion and the second plastic strain of the bending portion are smaller than the plastic strain threshold of the locking piece, using the initial locking piece finite element model as the locking piece finite element model;

[0060] S142. When any one of the first plastic strain at the bending portion and the second plastic strain at the bending portion is greater than the plastic strain threshold of the locking plate, a new locking plate material having a material elongation greater than that of the initial material of the locking plate is selected to correct the initial locking plate finite element model to obtain a locking plate finite element model that meets the plastic strain threshold of the locking plate.

[0061] In the specific implementation of step S1 of the present invention, when performing elastic-plastic analysis on the initial locking piece finite element model, the influence of large deformation of the locking piece is considered, the locking piece screw pressing position and the position in contact with the end surface of the substrate are constrained, and bending loads are applied to the end surfaces of the fixing claw and the positioning claw respectively for simulation analysis until the first bending load and the second bending load are obtained after the setting angles of the fixing claw and the positioning claw are bent to 90°, and the first plastic strain of the bending part of the fixing claw can be obtained according to the first bending load and the second bending load. and the first residual plastic stress , and the second plastic strain of the bending part of the positioning claw and the second residual plastic stress .

[0062] Plastic strain can be used to evaluate the material of the lock used to construct the initial lock finite element model. Specifically, if the plastic strain at the bending part of the fixed claw and the positioning claw is , All less than 0.5 (i.e., the plastic strain threshold is 0.5 times the elongation of the given cleat material), where is the elongation of the lock plate material, it means that the lock plate will not fail during normal bending; otherwise, the surface of the lock plate will be damaged during bending. In this case, the lock plate material needs to be replaced with a material with a higher elongation (such as >20%) until the plastic strain threshold is met and the revised cleat finite element model is obtained for subsequent strength reserve evaluation.

[0063] Furthermore, if the assembly operation is unreasonable during the bending process of the locking claw of the locking plate, the end face of the locking plate may be warped, which will cause the locking plate to bear a higher load at the screw pressing position. Therefore, the stress condition when the end face of the locking plate is warped needs to be considered when evaluating the strength reserve of the locking plate. The present invention uses a three-dimensional finite element model for analysis. The warped finite element model of the rotor connection structure needs to include screws, a locking plate model (that is, prepared by the locking plate material obtained after correction in step S1) and a matrix. The contact parts of each part need to be simulated using a contact unit, wherein the locking plate and the matrix only establish a contact unit at the screw pressing position). The screw preload is simulated by applying an axial interference amount to the mating end faces of the screw and the locking plate, and a load in the opposite direction to the bending of the locking plate is applied to the bending part of the locking plate positioning claw to perform elastic-plastic loading and unloading calculations. Specifically, a warped finite element model of the rotor connection structure is constructed using the locking plate finite element model, screws and matrix, including:

[0064] S21. Under the assembly condition, an axial interference is applied to the mating end faces of the locking plate and the screw, and a load in a direction opposite to the bending direction of the positioning claw is gradually applied to the bending position of the positioning claw until the end face of the locking plate is warped;

[0065] S22, unloading the load to obtain the initial warping of the locking piece, and calculating the residual plastic stress of the locking piece at the root of the screw compression according to the initial warping of the locking piece According to the initial warping of the locking piece, a warped finite element model including the locking piece finite element model, the screw and the substrate is established.

[0066] Furthermore, when conducting stress analysis of the locking piece under working conditions and establishing the contact unit between the locking piece and the end face of the substrate, it is necessary to consider the contact unit between the locking piece and the end face of the substrate (non-warping finite element model) and the contact unit between the locking piece and the substrate only at the screw tightening position (warping finite element model), so as to examine the working stress of the locking piece during normal installation and abnormal installation. After obtaining the finite element results of the locking piece in the two installation states of warping and non-warping, the corresponding stress can be extracted for subsequent analysis. Specifically, in step S2, the stress at the bending part of the positioning claw in the non-warping finite element model under working conditions is obtained. and the locking plate stress at the root of the screw in the warped finite element model ,include:

[0067] S23. Under working conditions, load the working load into the warping-free finite element model and load the axial interference on the mating end faces of the locking plate and the screw to obtain the stress at the bending part of the positioning claw. , Stress at the bending part of the positioning claw That is, when the locking piece fits well with the end surface of the base body, the stress at the bending part of the locking piece positioning claw is generated;

[0068] S24. Under working conditions, load the working load into the warped finite element model and load the axial interference on the mating end faces of the locking plate and the screw to obtain the locking plate stress at the root of the screw. , the locking plate stress at the root of the screw That is, the locking piece is warped, and the locking piece is stressed at the root of the screw compression when the locking piece and the base are only in contact at the screw compression part.

[0069] Further, see Figure 2 As shown, in step S3, the tensile properties of the locking piece are measured according to , fatigue limit of the locking piece, the elastic-plastic analysis results, the stress of the bending part of the positioning claw and the screw compression root lock plate stress , perform strength reserve assessment on the cleat, including:

[0070] S31, according to the second residual plastic stress in the elastic-plastic analysis results and the stress of the bending part of the positioning claw , calculate the effective stress at the bending part of the positioning claw ,in, .

[0071] S32, according to the screw tightening root lock plate stress Residual plastic stress of the locking piece at the root of the screw compression , calculate the effective stress of the locking piece at the root of the screw compression ,in, .

[0072] S33. Test the lock plate to obtain the actual tensile properties of the lock plate , according to the measured tensile properties of the locking piece , Effective stress at the bending part of the positioning claw And the effective stress of the screw compression root lock , static strength reserve assessment of the cleat.

[0073] S34, measuring tensile properties of the locking piece , fatigue limit of locking piece, effective stress of the bending part of positioning claw And the effective stress of the screw compression root lock , dynamic strength reserve assessment of the locking plate.

[0074] Furthermore, when evaluating the static strength reserve, the locking piece can be prepared by using the locking piece material that meets the plastic strain threshold determined in step S1, and the locking piece is tested to obtain the measured tensile properties of the locking piece. , and compare it with the effective stress and The results were compared when When the static strength reserve of the locking piece meets the requirements, otherwise there is a risk of overload fracture failure during operation. Specifically, in step S33, according to the measured tensile performance of the locking piece , Effective stress at the bending part of the positioning claw And the effective stress of the screw compression root lock , the static strength reserve assessment of the cleat includes the following steps:

[0075] S331, the effective stress of the bending part of the positioning claw The effective stress of the root lock piece compressed by the screw The maximum value of the measured tensile properties of the cleat If the maximum value is less than or equal to the measured tensile property of the cleat When the static strength reserve of the locking piece is judged to meet the design requirements;

[0076] S332: If the maximum value is greater than the measured tensile performance of the locking piece When the static strength reserve of the locking plate is judged to not meet the design requirements.

[0077] Furthermore, after evaluating the static strength reserve, considering that there is a certain gap between the locking plate and the substrate in actual situations, the locking plate may fail due to vibration fatigue, so it is also necessary to evaluate whether the dynamic strength reserve of the locking plate meets the requirements. And the measured tensile properties of the cleat , through the formula The allowable vibration stress of the locking plate can be obtained , according to the test to obtain the vibration stress of the locking plate (If there is no test data, consider the vibration stress of the lock plate not less than 20MPa ) Evaluate the dynamic strength reserve of the cleat. >2.5 indicates that the dynamic strength reserve of the locking piece meets the requirements, otherwise there is a risk of fatigue failure during operation. Specifically, in step S34, according to the measured tensile properties of the locking piece , fatigue limit of locking piece, effective stress of the bending part of positioning claw And the effective stress of the root lock piece compressed by the screw , the dynamic strength reserve assessment of the locking plate includes the following steps:

[0078] S341, measuring tensile properties of the locking piece , fatigue limit of locking piece, effective stress of the bending part of positioning claw And the effective stress of the root lock piece compressed by the screw , calculate the allowable vibration stress of the locking plate ;

[0079] S342. Test the lock plate to obtain the vibration stress of the lock plate (If there is no test data, consider the vibration stress of the lock plate not less than 20MPa ), if the locking piece allows vibration stress Vibration stress with the cleat When the ratio is greater than the ratio threshold, it is judged that the dynamic strength reserve of the lock piece meets the design requirements;

[0080] S343, if the locking piece allows vibration stress Vibration stress with the cleat When the ratio is greater than the ratio threshold, it is judged that the dynamic strength reserve of the lock plate does not meet the design requirements.

[0081] In an improved embodiment of the dynamic strength reserve of the locking plate, it is considered that after the locking plate is bent, micro cracks may appear at the bent portion. Therefore, when performing the dynamic strength reserve analysis, it is also possible to consider the initial micro cracks in the locking plate and the vibration stress. When evaluating whether the failure will expand rapidly, the initial crack size a is 0.38 mm (along the depth of the lock piece) according to the formula Determine the vibration stress of the clasp after bending The stress intensity factor generated , according to the formula Determine the working stress ratio R, and then combine it with the crack extension threshold of the locking piece , determine whether it satisfies If the requirements are met, it means that the dynamic strength reserve of the lock plate meets the requirements, otherwise there is a risk of fatigue failure during operation.

[0082] Based on the same inventive concept, an embodiment of the present invention also provides a lock plate strength assessment system for a rotor connection structure, as described in the following embodiments. Since the principle of solving the problem by the lock plate strength assessment system is similar to the lock plate strength assessment method disclosed in the above embodiments, the implementation of the lock plate strength assessment system can refer to the implementation of the lock plate strength assessment method, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0083] Figure 3 is a structural block diagram of a lock piece strength evaluation system for a rotor connection structure disclosed in an embodiment of the present invention, such as Figure 3 As shown, the lock plate strength assessment system includes a lock plate finite element model correction module 301, a rotor connection structure finite element model construction module 302, a stress calculation module 303 and a strength reserve assessment module 304, and the structure is described below.

[0084] The locking piece finite element model correction module 301 is used to perform elastic-plastic analysis on the constructed initial locking piece finite element model, and correct the initial locking piece finite element model according to the elastic-plastic analysis result to obtain the locking piece finite element model;

[0085] The rotor connection structure finite element model building module 302 is used to build a warped finite element model and a non-warped finite element model of the rotor connection structure through the locking piece finite element model, the screw and the matrix;

[0086] The stress calculation module 303 is used to obtain the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the locking piece at the root of the screw compression in the warping finite element model under working conditions;

[0087] The strength reserve evaluation module 304 is used to evaluate the strength reserve of the locking plate according to the measured tensile properties of the locking plate, the fatigue limit of the locking plate, the elastic-plastic analysis results, the stress of the bending part of the positioning claw and the locking plate stress at the root of the screw compression.

[0088] Furthermore, the lock piece finite element model correction module 301 uses the initial material of the lock piece to construct an initial lock piece finite element model according to the lock piece structure, and sets the lock piece plastic strain threshold according to the elongation of the lock piece material; through the finite element method, gradually apply bending loads to the fixed claw and the positioning claw of the initial lock piece finite element model, respectively, to obtain the first bending load corresponding to the fixed claw when it is bent to a set angle and the second bending load corresponding to the positioning claw when it is bent to a set angle; calculate the first plastic strain and the first residual plastic stress of the bending part of the fixed claw according to the first bending load, and calculate the second plastic strain and the second residual plastic stress of the bending part of the positioning claw according to the second bending load; evaluate the initial lock piece finite element model according to the first plastic strain of the bending part, the second plastic strain of the bending part and the lock piece plastic strain threshold, and modify the lock piece material for constructing the initial lock piece finite element model according to the evaluation result to obtain a lock piece finite element model that meets the lock piece plastic strain threshold.

[0089] Furthermore, the rotor connection structure finite element model construction module 302 is used to load axial interference onto the mating end faces of the locking plate and the screw under assembly conditions, and gradually load a load in the opposite direction of the bending direction of the positioning claw onto the bending position of the positioning claw until the end face of the locking plate warps; unload the load to obtain the initial warping of the locking plate, calculate the residual plastic stress of the locking plate at the root of the screw compression based on the initial warping of the locking plate, and establish a warped finite element model including the locking plate finite element model, the screw and the substrate based on the initial warping of the locking plate.

[0090] Further, the stress calculation module 303 is used to calculate the effective stress of the bent portion of the positioning claw according to the second residual plastic stress in the elastic-plastic analysis result and the stress of the bent portion of the positioning claw; calculate the effective stress of the screw compression root locking piece according to the screw compression root locking piece stress and the residual plastic stress of the screw compression root locking piece;

[0091] Furthermore, the strength reserve assessment module 304 is used to test the locking plate to obtain the actual tensile properties of the locking plate, and to perform a static strength reserve assessment on the locking plate based on the actual tensile properties of the locking plate, the effective stress at the bending part of the positioning claw, and the effective stress at the root of the locking plate at the compression of the screw; and to perform a dynamic strength reserve assessment on the locking plate based on the actual tensile properties of the locking plate, the fatigue limit of the locking plate, the effective stress at the bending part of the positioning claw, and the effective stress at the root of the locking plate at the compression of the screw.

[0092] The lock plate strength assessment method of the rotor connection structure of the present invention performs assessments on three aspects: lock plate material, lock plate static strength reserve, and lock plate dynamic strength reserve. This can achieve accurate assessment of lock plate risks under working conditions and provide data guidance for reasonable design of lock plates.

[0093] In this embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, any of the above-mentioned methods for evaluating the strength of a locking piece of a rotor connection structure is implemented.

[0094] Specifically, the computer device may be a computer terminal, a server or a similar computing device.

[0095] In this embodiment, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program for executing any of the above-mentioned methods for evaluating the strength of a locking piece of a rotor connection structure.

[0096] Specifically, computer-readable storage media include permanent and non-permanent, removable and non-removable media that can be used to store information by any method or technology. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer-readable storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable storage media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0097] Obviously, those skilled in the art should understand that the modules or steps of the above-mentioned embodiments of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order from that here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. In this way, the embodiments of the present invention are not limited to any specific combination of hardware and software.

[0098] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for evaluating the strength of a locking piece of a rotor connection structure, characterized in that: include: An elastic-plastic analysis is performed on the constructed initial locking piece finite element model, and the initial locking piece finite element model is modified according to the elastic-plastic analysis result to obtain the locking piece finite element model, including: using the initial material of the locking piece to construct the initial locking piece finite element model according to the locking piece structure, and setting the locking piece plastic strain threshold according to the elongation of the locking piece material; using the finite element method, gradually applying bending loads to the fixed claw and the positioning claw of the initial locking piece finite element model, respectively, to obtain a first bending load corresponding to when the fixed claw is bent to a set angle and a second bending load corresponding to when the positioning claw is bent to a set angle; calculating the first plastic strain and the first residual plastic stress of the bending part of the fixing claw according to the first bending load, and calculating the second plastic strain and the second residual plastic stress of the bending part of the positioning claw according to the second bending load; evaluating the initial locking piece finite element model according to the first plastic strain of the bending part, the second plastic strain of the bending part and the locking piece plastic strain threshold, and modifying the locking piece material for constructing the initial locking piece finite element model according to the evaluation result to obtain a locking piece finite element model that meets the locking piece plastic strain threshold; A non-warping finite element model and a warping finite element model of the rotor connection structure are constructed by using the locking piece finite element model, the screw and the matrix, and the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the locking piece at the root of the screw pressing in the warping finite element model are obtained under working conditions; The strength reserve of the locking piece is evaluated based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the elastic-plastic analysis results, the stress at the bending part of the positioning claw and the locking piece stress at the root of the screw compression.

2. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 1, characterized in that: According to the first plastic strain of the bending part, the second plastic strain of the bending part and the plastic strain threshold of the locking piece, the initial locking piece finite element model is evaluated, and according to the evaluation result, the locking piece material for constructing the initial locking piece finite element model is modified to obtain the locking piece finite element model that meets the locking piece plastic strain threshold, including: Comparing the first plastic strain of the bending part and the second plastic strain of the bending part with a plastic strain threshold, and when both the first plastic strain of the bending part and the second plastic strain of the bending part are smaller than the plastic strain threshold of the locking piece, using the initial locking piece finite element model as the locking piece finite element model; When any one of the first plastic strain at the bending portion and the second plastic strain at the bending portion is greater than the plastic strain threshold of the locking plate, a new locking plate material having a material elongation greater than that of the initial material of the locking plate is selected to correct the initial locking plate finite element model to obtain a locking plate finite element model that meets the plastic strain threshold of the locking plate.

3. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 1, characterized in that: The plastic strain threshold of the locking plate is 0.5 times the elongation of the locking plate material, and the set angle is 90°.

4. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 1, characterized in that: The warped finite element model of the rotor connection structure is constructed by using the locking piece finite element model, the screw and the matrix, including: Under the assembly condition, an axial interference is applied to the mating end faces of the locking plate and the screw, and a load opposite to the bending direction of the positioning claw is gradually applied to the bending position of the positioning claw until the end face of the locking plate is warped; The initial warping of the locking piece is obtained by unloading the load, the residual plastic stress of the locking piece at the root of the screw compression is calculated according to the initial warping of the locking piece, and a warped finite element model including the locking piece finite element model, the screw and the substrate is established according to the initial warping of the locking piece.

5. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 4, characterized in that: Obtaining the stress of the bending part of the positioning claw in the non-warping finite element model and the stress of the locking piece at the root of the screw compression in the warping finite element model under working conditions, including: Under working conditions, a working load is applied to the warpage-free finite element model and an axial interference is applied to the mating end faces of the locking plate and the screw to obtain stress at the bending portion of the positioning claw; Under working conditions, a working load is added to the warped finite element model and an axial interference is added to the mating end faces of the locking plate and the screw to obtain the locking plate stress at the screw compression root.

6. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 4, characterized in that: Based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the elastic-plastic analysis results, the stress at the bending part of the positioning claw and the locking piece stress at the root of the screw compression, the strength reserve of the locking piece is evaluated, including: According to the second residual plastic stress and the stress at the bending part of the positioning claw in the elastic-plastic analysis results, the effective stress at the bending part of the positioning claw is calculated; Calculate the effective stress of the screw compression root locking piece according to the screw compression root locking piece stress and the residual plastic stress of the screw compression root locking piece; The locking piece is tested to obtain the measured tensile properties of the locking piece, and the static strength reserve of the locking piece is evaluated based on the measured tensile properties of the locking piece, the effective stress at the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression; The dynamic strength reserve of the lock piece is evaluated based on the measured tensile properties of the lock piece, the fatigue limit of the lock piece, the effective stress at the bending part of the positioning claw, and the effective stress of the lock piece at the root of the screw compression.

7. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 6, characterized in that: Based on the measured tensile properties of the locking piece, the effective stress at the bending part of the positioning claw and the effective stress of the locking piece at the root of the screw compression, the static strength reserve of the locking piece is evaluated, including: The maximum value of the effective stress at the bending part of the positioning claw and the effective stress of the locking piece at the root of the screw compression is compared with the measured tensile property of the locking piece. If the maximum value is less than or equal to the measured tensile property of the locking piece, it is judged that the static strength reserve of the locking piece meets the design requirements. If the maximum value is greater than the actually measured tensile property of the locking piece, it is determined that the static strength reserve of the locking piece does not meet the design requirements.

8. The method for evaluating the strength of a locking piece of a rotor connection structure according to claim 6, characterized in that: Based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the effective stress at the bending part of the positioning claw and the effective stress of the locking piece at the root of the screw compression, the dynamic strength reserve of the locking piece is evaluated, including: Calculate the allowable vibration stress of the locking piece according to the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the effective stress at the bending part of the positioning claw, and the effective stress of the locking piece at the root of the screw compression; The locking piece is tested to obtain the vibration stress of the locking piece. If the ratio of the allowable vibration stress of the locking piece to the vibration stress of the locking piece is greater than a ratio threshold, it is determined that the dynamic strength reserve of the locking piece meets the design requirements. If the ratio of the allowable vibration stress of the locking plate to the vibration stress of the locking plate is greater than a ratio threshold, it is determined that the dynamic strength reserve of the locking plate does not meet the design requirements.

9. A lock plate strength evaluation system for a rotor connection structure, characterized in that: include: A locking piece finite element model correction module, the locking piece finite element model correction module is used to perform elastic-plastic analysis on the constructed initial locking piece finite element model, and correct the initial locking piece finite element model according to the elastic-plastic analysis result to obtain the locking piece finite element model, including: using the initial material of the locking piece to construct the initial locking piece finite element model according to the locking piece structure, and setting the locking piece plastic strain threshold according to the elongation of the locking piece material; gradually applying bending loads to the fixed claw and the positioning claw of the initial locking piece finite element model by the finite element method, and obtaining the first bending load and the positioning claw corresponding to the fixed claw being bent to the set angle. a second bending load corresponding to when the locking piece is bent to a set angle; calculating a first plastic strain and a first residual plastic stress at a bending portion of the fixing claw according to the first bending load, and calculating a second plastic strain and a second residual plastic stress at a bending portion of the positioning claw according to the second bending load; evaluating the initial locking piece finite element model according to the first plastic strain at the bending portion, the second plastic strain at the bending portion, and the plastic strain threshold of the locking piece, and modifying the locking piece material for constructing the initial locking piece finite element model according to the evaluation result to obtain a locking piece finite element model that meets the plastic strain threshold of the locking piece; A rotor connection structure finite element model building module, wherein the rotor connection structure finite element model building module is used to build a non-warping finite element model and a warping finite element model of the rotor connection structure through the locking piece finite element model, the screw and the matrix; A stress calculation module, the stress calculation module is used to obtain the stress of the bending part of the positioning claw in the non-warping finite element model under working conditions and the stress of the locking piece at the root of the screw compression in the warping finite element model; A strength reserve assessment module is used to assess the strength reserve of the locking piece based on the measured tensile properties of the locking piece, the fatigue limit of the locking piece, the elastic-plastic analysis results, the stress at the bending part of the positioning claw, and the locking piece stress at the root of the screw compression.

Images