Simulation evaluation method and device for heat shield in automobile power assembly

Abstract

The invention provides a simulation evaluation method and device for a heat shield in an automobile power assembly, and the method comprises the steps: constructing a finite element simulation model of an automobile power assembly system; aiming at each automobile power part, applying a corresponding vibration excitation load to the automobile power part according to the type of the automobile power part; and carrying out vibration simulation on the finite element simulation model, calculating a slippage safety coefficient corresponding to each bolt arranged on the heat shield of the automobile power part, and when the slippage safety coefficient corresponding to each bolt reaches a safety coefficient threshold value, considering that the heat shield of the automobile power part meets the design requirement. According to the method and the device, through early-stage design reliability evaluation, the problems of cracking, bolt loosening and the like of the heat insulation cover in actual work can be avoided, and the subsequent production period is shortened.

Description

Technical Field

[0001] The present application relates to the field of automobile simulation technology, and in particular to a simulation evaluation method and device for a heat shield in an automobile powertrain. Background Art

[0002] For extended-range hybrid vehicles, the use of heat shields is essential to avoid the heat load of the engine exhaust system on surrounding parts.

[0003] The heat shield design for hybrid vehicle powertrain is generally installed on the engine and electric drive. At present, the heat shield is generally designed as a special-shaped structure according to different vehicle models and parts space layout. It is not comprehensive to judge the layout of the bolt points on the heat shield and whether the model and process match only by experience. If the design is insufficient, it will cause safety risks such as cracking and loosening of bolts in actual work. Summary of the invention

[0004] In view of this, the purpose of this application is to provide a simulation evaluation method and device for a heat shield in an automobile powertrain. During the simulation process, the excitation conditions of different parts of a hybrid vehicle on the road are comprehensively considered, so that the model simulation is more consistent with the actual stress conditions of the heat shield, and the evaluation results are more accurate. The safety factor of the bolts installed on the heat shield is calculated, and the design reliability of the heat shield can be evaluated through simulation, which can avoid cracking of the heat shield and loose bolts in actual work, and shorten the subsequent production cycle.

[0005] In a first aspect, an embodiment of the present application provides a simulation evaluation method for a heat shield in an automobile powertrain, the simulation evaluation method comprising:

[0006] Constructing a finite element simulation model of an automobile powertrain system; wherein the finite element simulation model includes a plurality of automobile power parts, each automobile power part is provided with a heat shield, and bolts are provided at preset points of each heat shield;

[0007] For each automotive power part, a corresponding vibration excitation load is applied to the automotive power part according to the type of the automotive power part;

[0008] Vibration simulation is performed on the finite element simulation model, and a sliding safety factor corresponding to each bolt arranged on the heat shield of the automotive power part is calculated. When the sliding safety factor corresponding to each bolt reaches a safety factor threshold, it is considered that the heat shield of the automotive power part meets the design requirements.

[0009] Furthermore, the vibration excitation load includes engine vibration excitation, road surface non-periodic vibration excitation and motor rotor periodic rotation excitation; applying a corresponding vibration excitation load to the automotive power part according to the type of the automotive power part includes:

[0010] When the automobile power part is a range extender, applying the engine vibration excitation to the automobile power part;

[0011] When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

[0012] Furthermore, after applying the corresponding vibration excitation load to each automotive power part, the simulation evaluation method further includes:

[0013] Performing modal analysis on the heat shield to determine a current vibration frequency of the heat shield;

[0014] When the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is less than or equal to a preset frequency threshold, the structure and position of the heat insulation cover are adjusted, and the process returns to the step of performing modal analysis on the heat insulation cover to determine the current vibration frequency of the heat insulation cover until the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is greater than the preset frequency threshold.

[0015] Furthermore, when performing vibration simulation on the finite element simulation model, the simulation evaluation method further includes:

[0016] Calculating the stress value of each node in the heat shield based on the frequency response simulation result;

[0017] When there are nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold, the structure and position of the heat insulation cover are adjusted, and the step of performing vibration simulation on the finite element simulation model is returned to be executed until there are no nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold.

[0018] Furthermore, the calculation of the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part includes:

[0019] For each bolt, the first tangential force component and the second tangential force component of the bolt along the tangent plane direction are calculated by vibration simulation;

[0020] Calculating a tangential resultant force of the bolt based on the first tangential force component and the second tangential force component;

[0021] Calculating the friction force of the bolt transmitting the transverse load on the section based on the friction coefficient between the bolt and the heat shield, the pre-tightening force of the bolt, and the discreteness of the bolt;

[0022] The ratio between the tangential resultant force and the friction force is taken as the slip safety factor corresponding to the bolt.

[0023] Furthermore, after calculating the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part, the simulation evaluation method further includes:

[0024] For each bolt, when the slip safety factor corresponding to the bolt does not reach the safety factor threshold, the model and torque range of the target bolt installed at the preset point where the bolt is located are determined based on the support reaction force received by the bolt.

[0025] In a second aspect, the embodiment of the present application further provides a simulation evaluation device for a heat shield in an automobile powertrain, the simulation evaluation device comprising:

[0026] A model building module, used to build a finite element simulation model of an automobile powertrain system; wherein the finite element simulation model includes a plurality of automobile power parts, each of which is provided with a heat shield, and bolts are provided at preset points of each heat shield;

[0027] An excitation applying module, used for applying a corresponding vibration excitation load to each automotive power part according to the type of the automotive power part;

[0028] The safety factor calculation module is used to perform vibration simulation on the finite element simulation model and calculate the sliding safety factor corresponding to each bolt arranged on the heat shield of the automotive power part. When the sliding safety factor corresponding to each bolt reaches the safety factor threshold, it is considered that the heat shield of the automotive power part meets the design requirements.

[0029] Furthermore, the vibration excitation load includes engine vibration excitation, road surface non-periodic vibration excitation and motor rotor periodic rotation excitation; when the excitation applying module is used to apply the corresponding vibration excitation load to the automotive power part according to the type of the automotive power part, the excitation applying module is also used to:

[0030] When the automobile power part is a range extender, applying the engine vibration excitation to the automobile power part;

[0031] When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

[0032] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate via the bus, and when the machine-readable instructions are executed by the processor, the steps of the simulation evaluation method for the heat shield in the automotive powertrain are performed as described above.

[0033] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the simulation evaluation method for a heat shield in an automobile powertrain as described above are executed.

[0034] The embodiment of the present application provides a simulation evaluation method and device for a heat shield in an automobile powertrain. First, a finite element simulation model of an automobile powertrain system is constructed; wherein the finite element simulation model includes a plurality of automobile power parts, each of which is provided with a heat shield, and bolts are provided at preset points of each heat shield; then, for each automobile power part, a corresponding vibration excitation load is applied to the automobile power part according to the type of the automobile power part; vibration simulation is performed on the finite element simulation model, and a sliding safety factor corresponding to each bolt provided on the heat shield of the automobile power part is calculated; when the sliding safety factor corresponding to each bolt reaches a safety factor threshold, it is considered that the heat shield of the automobile power part meets the design requirements.

[0035] During the simulation process, this application comprehensively considers the excitation conditions of different parts of the hybrid vehicle on the road, so that the model simulation is more consistent with the actual stress conditions of the heat shield, and the evaluation results are more accurate. The safety factor of the bolts installed on the heat shield is calculated, and the design reliability of the heat shield can be evaluated through simulation. In this way, through the early design reliability evaluation, problems such as cracking and loose bolts in the heat shield can be avoided in actual work, shortening the subsequent production cycle.

[0036] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] 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. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1A flowchart of a simulation evaluation method for a heat shield in an automobile powertrain provided in an embodiment of the present application;

[0039] Figure 2 A schematic diagram of a finite element simulation model provided in an embodiment of the present application;

[0040] Figure 3 A schematic structural diagram of a simulation evaluation device for a heat shield in an automobile powertrain provided in an embodiment of the present application;

[0041] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0043] First, the application scenarios to which the present application is applicable are introduced. The present application can be applied in the field of automobile simulation technology.

[0044] For extended-range hybrid vehicles, the use of heat shields is essential to avoid the heat load of the engine exhaust system on surrounding parts.

[0045] According to research, the heat shield design for hybrid vehicle powertrain is generally installed on the engine and electric drive. At present, the heat shield is generally designed as a special-shaped structure according to different vehicle models and parts space layout. It is not comprehensive to judge the layout of the bolt points on the heat shield and whether the model and process match only by experience. If the design is insufficient, it will cause safety risks such as cracking and loosening of bolts in actual work.

[0046] Based on this, an embodiment of the present application provides a simulation evaluation method for a heat shield in an automobile powertrain. The design reliability of the heat shield is evaluated by simulation, which can avoid problems such as cracking and loose bolts of the heat shield in actual work and shorten the subsequent production cycle.

[0047] See also Figure 1 , Figure 1This is a flow chart of a simulation evaluation method for a heat shield in an automobile powertrain provided in an embodiment of the present application. Figure 1 As shown in , the simulation evaluation method provided by the embodiment of the present application includes:

[0048] S101, construct a finite element simulation model of the automobile powertrain system.

[0049] Here, the finite element simulation model is a mathematical model used to simulate and analyze complex structures and systems. According to the embodiment provided by the present application, the finite element simulation model of the automobile powertrain system includes a plurality of automobile power parts, each of which is provided with a heat shield, and bolts are provided at preset points of each heat shield.

[0050] The heat source of the extended-range hybrid powertrain is generally the engine, of which the exhaust system has the widest impact. The exhaust system is discharged from the exhaust side of the engine at the front of the car through the electric drive assembly, battery assembly, etc. to the rear of the car. The parts along its path need to be thermally protected, usually with a heat shield to prevent damage to the low-melting-point parts of the electric drive assembly that are susceptible to high temperatures, such as leakage from the shell caused by the melting of the curing glue. Therefore, in addition to heat insulation at the heat source end, it is also necessary to heat-insulate the parts close to the electric drive assembly end. Please refer to Figure 2 , Figure 2 A schematic diagram of a finite element simulation model provided in an embodiment of the present application. Figure 2 As shown, when the automobile powertrain system is a range-extended hybrid powertrain system, the automobile powertrain system includes a range extender and a drive motor, a heat shield 1 is provided on the range extender, and a plurality of preset points are provided on the heat shield 1 for placing bolts, and a heat shield 2 is provided on the drive motor, and a plurality of preset points are provided on the heat shield 2 for placing bolts.

[0051] Regarding the above step S101, during the specific implementation, a finite element simulation model of the automobile powertrain system is first constructed, in which a plurality of automobile power parts are arranged, each automobile power part is provided with a heat shield, and bolts are arranged at preset points of each heat shield.

[0052] S102, for each automobile power part, applying a corresponding vibration excitation load to the automobile power part according to the type of the automobile power part.

[0053] Here, vibration excitation load refers to the dynamic load applied to the structure in vibration simulation to simulate the vibration excitation of the structure in actual use. Vibration excitation load can be periodic, random or transient. By applying vibration excitation load, the response of the structure under different vibration conditions can be analyzed and its dynamic performance and reliability can be evaluated.

[0054] Regarding the above step S102, during specific implementation, for each automobile power part, a corresponding vibration excitation load is applied to the automobile power part according to the type of the automobile power part.

[0055] Here, according to the embodiment provided by the present application, since the exhaust system of a car has different fixed positions of the affected components from the front to the rear of the car, the excitation received by the heat shields on different car power parts varies depending on the opponent parts.

[0056] Specifically, the vibration excitation load includes engine vibration excitation, road non-periodic vibration excitation and motor rotor periodic rotation excitation. With respect to the above S102, applying a corresponding vibration excitation load to the automobile power part according to the type of the automobile power part includes:

[0057] Step 1021: When the automobile power part is a range extender, the engine vibration excitation is applied to the automobile power part.

[0058] Here, when the automobile power part is a range extender, the excitation source of the heat shield on the range extender is mainly generated by the engine body, and only the engine excitation is considered. With respect to the above step 1021, in the specific implementation, when the automobile power part is a range extender, the engine vibration excitation is applied to the automobile power part, which is characterized by second-order reciprocating motion excitation. When applying the engine vibration excitation, the frequency response analysis method is adopted.

[0059] Step 1022: When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

[0060] Here, when the automobile power part is a drive motor, the excitation source of the heat shield on the drive motor mainly considers the non-periodic excitation of the road surface and the periodic excitation generated by the motor body rotor. With respect to the above step 1022, when the automobile power part is a drive motor, the automobile power part is subjected to non-periodic vibration excitation of the road surface and periodic rotation excitation of the motor rotor, and the random vibration and sweep frequency methods can be used for analysis, which is more in line with the actual stress condition of the heat shield, and the evaluation result obtained is more accurate.

[0061] As an optional embodiment, after applying the corresponding vibration excitation load to each automotive power part, the simulation evaluation method further includes:

[0062] A: Perform modal analysis on the heat shield to determine the current vibration frequency of the heat shield.

[0063] B: When the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is less than or equal to the preset frequency threshold, the structure and position of the heat insulation cover are adjusted, and the process returns to the step of performing modal analysis on the heat insulation cover to determine the current vibration frequency of the heat insulation cover, until the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is greater than the preset frequency threshold.

[0064] After applying the corresponding vibration excitation load to each automotive power part, it is necessary to perform a modal analysis on the heat insulation cover to avoid the resonance interval between the heat insulation cover and the automotive power. For the above steps A-B, in the specific implementation, a modal analysis is performed on the heat insulation cover to determine the current vibration frequency of the heat insulation cover. When the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is less than or equal to the preset frequency threshold, the heat insulation cover will resonate with the automotive power part. At this time, the structure and position of the heat insulation cover need to be adjusted, and the step of performing a modal analysis on the heat insulation cover in the above step A to determine the current vibration frequency of the heat insulation cover is returned. Here, the optimized heat insulation cover can be obtained by adjusting the structure and position of the heat insulation cover, and the optimized heat insulation cover is returned to step A to perform a modal analysis again to determine the current vibration frequency of the optimized heat insulation cover, and then the current vibration frequency is compared with the vibration frequency of the vibration excitation load again until the difference between the current vibration frequency and the vibration frequency of the vibration excitation load is greater than the preset frequency threshold.

[0065] S103, performing vibration simulation on the finite element simulation model, and calculating the sliding safety factor corresponding to each bolt arranged on the heat shield of the automobile power part. When the sliding safety factor corresponding to each bolt reaches the safety factor threshold, it is considered that the heat shield of the automobile power part meets the design requirements.

[0066] Here, the bolts installed on the heat shield are often installed on thin-walled parts and are subjected to vibration loads. The safety factor threshold of such bolts is larger than that of other bolts, and a certain safety factor threshold needs to be increased to evaluate their loosening. For example, assuming that the safety factor threshold of general bolts is 1.1, the safety factor threshold of bolts installed on vibrating thin-walled parts is 1.5.

[0067] For the above step S103, during the specific implementation, the finite element simulation model of the automobile powertrain system is subjected to vibration simulation, and the slip safety factor corresponding to each bolt set on the heat shield of the automobile power part is calculated. The slip safety factor corresponding to each bolt is compared with the safety factor threshold. When the slip safety factor of each bolt reaches the safety factor threshold, it means that the bolt is safe, and it is considered that the heat shield of the automobile power part meets the design requirements. In the subsequent production process of the automobile powertrain system, the finite element simulation model is used as a benchmark, and the early design reliability evaluation is performed to avoid problems such as cracking of the heat shield and loose bolts in actual work, shorten the production cycle and reduce the design cost.

[0068] As an optional embodiment, when performing vibration simulation on the finite element simulation model, the simulation evaluation method further includes:

[0069] I: Calculate the stress value of each node in the heat shield based on the frequency response simulation results.

[0070] II: When there are nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold, adjust the structure and position of the heat insulation cover, and return to the step of performing vibration simulation on the finite element simulation model until there are no nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold.

[0071] When performing vibration simulation on the finite element simulation model, it is necessary to optimize the stress concentration area of ​​the heat insulation cover to reduce the risk of cracking of the heat insulation cover and improve the accuracy of the simulation evaluation of the heat insulation cover. For the above steps I-II, in the specific implementation, the stress value of each node in the heat insulation cover is calculated based on the frequency response simulation results of the vibration simulation. When there are nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold, the structure and position of the heat insulation cover are adjusted, and the step of performing vibration simulation on the finite element simulation model described in the above step S103 is returned to execute. Here, the optimized heat insulation cover can be obtained by adjusting the structure and position of the heat insulation cover, and returning to step S103 to re-perform vibration simulation on the finite element simulation model to recalculate the stress value of each node in the optimized heat insulation cover until there are no nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold.

[0072] As an optional embodiment, with respect to the above step S103, the calculation of the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part includes:

[0073] Step 1031: For each bolt, calculate the first tangential force component and the second tangential force component of the bolt along the tangent plane direction through vibration simulation.

[0074] Step 1032: Calculate the tangential resultant force of the bolt based on the first tangential component force and the second tangential component force.

[0075] In the above steps 1031 to 1032, when performing vibration simulation on the finite element simulation model, for each bolt on the heat shield of the automotive power part, the first tangential force component RF1 and the second tangential force component RF2 of the bolt along the tangent direction are calculated by vibration simulation. Then, the tangential resultant force of the bolt is calculated based on the first tangential force component RF1 and the second tangential force component RF2. Specifically, the tangential resultant force F of the bolt is K Calculated by the following formula:

[0076]

[0077] Step 1033: Calculate the friction force of the bolt transmitting the transverse load on the section based on the friction coefficient between the bolt and the heat shield, the pre-tightening force of the bolt, and the discreteness of the bolt.

[0078] Here, the bolt preload is the preload along the bolt axis generated between the bolt and the connected part under the action of the tightening torque during the bolt tightening process. The magnitude of the preload is related to the tightening torque of the bolt, the friction between the bolt and the nut, and the friction between the nut and the connected part. Preloading can improve the reliability, anti-loosening ability and fatigue strength of the bolt connection, and enhance the tightness and rigidity of the connection. Therefore, in order to determine the forces on different parts under different working conditions, it is necessary to determine the appropriate bolt preload range to achieve the optimal solution while ensuring the normal operation of the parts.

[0079] For the above step 1033, in the specific implementation, the friction force of the bolt transmitting the lateral load on the section is calculated based on the friction coefficient between the bolt and the heat shield, the preload force of the bolt, and the discreteness of the bolt. Specifically, the minimum preload force after the bolt is tightened is set to F Mmin , the maximum preload is F Mmax The friction coefficient between the bolt and the heat shield is μ T The discreteness of the bolt is K. The friction force F of the bolt transmitting the lateral load on the section is calculated by the following formula: KQerf :

[0080] F KQerf =F M ·μ T ·K

[0081] Step 1034: taking the ratio of the tangential resultant force to the friction force as the slip safety factor corresponding to the bolt.

[0082] Regarding the above step 1034, during the specific implementation, the tangential force FK and friction force F KQerf After calculation, the ratio between the tangential resultant force and the friction force is taken as the slip safety factor corresponding to the bolt. Specifically, the slip safety factor S corresponding to the bolt is G Calculated by the following formula:

[0083]

[0084] As an optional embodiment, after calculating the sliding safety factor corresponding to each bolt arranged on the heat shield of the automotive power part, the simulation evaluation method further includes:

[0085] For each bolt, when the slip safety factor corresponding to the bolt does not reach the safety factor threshold, the model and torque range of the target bolt installed at the preset point where the bolt is located are determined based on the support reaction force received by the bolt.

[0086] Here, the target bolt refers to a more suitable bolt installed at a preset point in the finite element simulation model when the slip safety factor of the bolt set at the preset point does not reach the safety factor threshold.

[0087] With respect to the above steps, during the specific implementation, for each bolt, when the slip safety factor corresponding to the bolt does not reach the safety factor threshold, the type of bolt that should be installed at the preset point can be inferred based on the support reaction force received by the bolt. That is, the model and torque range of the target bolt installed at the preset point where the bolt is located are determined based on the support reaction force received by the bolt. In this way, since the bolts are replaced by rigid units in the actual modeling process, there is no need to load the bolts, only to extract the reaction force results received by the rigid units at that location. Therefore, the originally preset (or undetermined model) bolts can be inferred based on the support reaction force received by the bolts to find the appropriate target bolts installed at the preset point.

[0088] The simulation evaluation method of the heat shield in the automobile powertrain provided in the embodiment of the present application comprises the following steps: first, constructing a finite element simulation model of the automobile powertrain system; wherein the finite element simulation model comprises a plurality of automobile power parts, each of which is provided with a heat shield, and bolts are provided at preset points of each heat shield; then, for each automobile power part, applying a corresponding vibration excitation load to the automobile power part according to the type of the automobile power part; performing vibration simulation on the finite element simulation model, and calculating the sliding safety factor corresponding to each bolt provided on the heat shield of the automobile power part; when the sliding safety factor corresponding to each bolt reaches the safety factor threshold, it is considered that the heat shield of the automobile power part meets the design requirements.

[0089] During the simulation process, this application comprehensively considers the excitation conditions of different parts of the hybrid vehicle on the road, so that the model simulation is more consistent with the actual stress conditions of the heat shield, and the evaluation results are more accurate. The safety factor of the bolts installed on the heat shield is calculated, and the design reliability of the heat shield can be evaluated through simulation. In this way, through the early design reliability evaluation, problems such as cracking and loose bolts in the heat shield can be avoided in actual work, shortening the subsequent production cycle.

[0090] See also Figure 3 , Figure 3 This is a schematic diagram of the structure of a simulation evaluation device for a heat shield in an automobile powertrain provided in an embodiment of the present application. Figure 3 As shown in , the simulation evaluation device 300 includes:

[0091] The model building module 301 is used to build a finite element simulation model of an automobile powertrain system; wherein the finite element simulation model includes a plurality of automobile power parts, each automobile power part is provided with a heat shield, and bolts are provided at preset points of each heat shield;

[0092] An excitation applying module 302 is used to apply a corresponding vibration excitation load to each automotive power part according to the type of the automotive power part;

[0093] The safety factor calculation module 303 is used to perform vibration simulation on the finite element simulation model and calculate the sliding safety factor corresponding to each bolt set on the heat shield of the automotive power part. When the sliding safety factor corresponding to each bolt reaches the safety factor threshold, it is considered that the heat shield of the automotive power part meets the design requirements.

[0094] Further, the vibration excitation load includes engine vibration excitation, road surface non-periodic vibration excitation and motor rotor periodic rotation excitation; when the excitation applying module 302 is used to apply the corresponding vibration excitation load to the automobile power part according to the type of the automobile power part, the excitation applying module 302 is also used to:

[0095] When the automobile power part is a range extender, applying the engine vibration excitation to the automobile power part;

[0096] When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

[0097] Furthermore, the simulation evaluation device 300 further includes a modal analysis module. After applying a corresponding vibration excitation load to each automotive power part, the modal analysis module is used to:

[0098] Performing modal analysis on the heat shield to determine a current vibration frequency of the heat shield;

[0099] When the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is less than or equal to a preset frequency threshold, the structure and position of the heat insulation cover are adjusted, and the process returns to the step of performing modal analysis on the heat insulation cover to determine the current vibration frequency of the heat insulation cover until the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is greater than the preset frequency threshold.

[0100] Furthermore, the simulation evaluation device 300 further includes a model adjustment module. When the vibration simulation is performed on the finite element simulation model, the model adjustment module is used to:

[0101] Calculating the stress value of each node in the heat shield based on the frequency response simulation result;

[0102] When there are nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold, the structure and position of the heat insulation cover are adjusted, and the step of performing vibration simulation on the finite element simulation model is returned to be executed until there are no nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold.

[0103] Furthermore, when the safety factor calculation module 303 is used to calculate the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part, the safety factor calculation module 303 is also used to:

[0104] For each bolt, the first tangential force component and the second tangential force component of the bolt along the tangent plane direction are calculated by vibration simulation;

[0105] Calculating a tangential resultant force of the bolt based on the first tangential force component and the second tangential force component;

[0106] Calculating the friction force of the bolt transmitting the transverse load on the section based on the friction coefficient between the bolt and the heat shield, the pre-tightening force of the bolt, and the discreteness of the bolt;

[0107] The ratio between the tangential resultant force and the friction force is taken as the slip safety factor corresponding to the bolt.

[0108] Furthermore, the evaluation simulation device 300 further includes a bolt adjustment module. After calculating the slip safety factor corresponding to each bolt disposed on the heat shield of the automotive power part, the bolt adjustment module is used to:

[0109] For each bolt, when the slip safety factor corresponding to the bolt does not reach the safety factor threshold, the model and torque range of the target bolt installed at the preset point where the bolt is located are determined based on the support reaction force received by the bolt.

[0110] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 4 As shown in , the electronic device 400 includes a processor 410 , a memory 420 and a bus 430 .

[0111] The memory 420 stores machine-readable instructions executable by the processor 410. When the electronic device 400 is running, the processor 410 communicates with the memory 420 via the bus 430. When the machine-readable instructions are executed by the processor 410, the above-mentioned Figure 1 The steps of the simulation evaluation method for the heat shield in the automobile powertrain in the method embodiment shown in the embodiment and the specific implementation thereof can be referred to the method embodiment, which will not be described in detail here.

[0112] The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the computer program can execute the above-mentioned Figure 1 The steps of the simulation evaluation method for the heat shield in the automobile powertrain in the method embodiment shown in the embodiment and the specific implementation thereof can be referred to the method embodiment, which will not be described in detail here.

[0113] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0114] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0115] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0116] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0117] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0118] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A simulation evaluation method for a heat shield in an automobile powertrain, characterized in that: The simulation evaluation method comprises: Constructing a finite element simulation model of an automobile powertrain system; wherein the finite element simulation model includes a plurality of automobile power parts, each automobile power part is provided with a heat shield, and bolts are provided at preset points of each heat shield; For each automotive power part, a corresponding vibration excitation load is applied to the automotive power part according to the type of the automotive power part; Vibration simulation is performed on the finite element simulation model, and a sliding safety factor corresponding to each bolt arranged on the heat shield of the automotive power part is calculated. When the sliding safety factor corresponding to each bolt reaches a safety factor threshold, it is considered that the heat shield of the automotive power part meets the design requirements.

2. The simulation evaluation method according to claim 1, characterized in that: The vibration excitation load includes engine vibration excitation, road surface non-periodic vibration excitation and motor rotor periodic rotation excitation; The step of applying a corresponding vibration excitation load to the automobile power part according to the type of the automobile power part comprises: When the automobile power part is a range extender, applying the engine vibration excitation to the automobile power part; When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

3. The simulation evaluation method according to claim 1, characterized in that: After applying a corresponding vibration excitation load to each automotive power part, the simulation evaluation method further includes: Performing modal analysis on the heat shield to determine a current vibration frequency of the heat shield; When the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is less than or equal to a preset frequency threshold, the structure and position of the heat insulation cover are adjusted, and the process returns to the step of performing modal analysis on the heat insulation cover to determine the current vibration frequency of the heat insulation cover until the difference between the current vibration frequency of the heat insulation cover and the vibration frequency of the vibration excitation load is greater than the preset frequency threshold.

4. The simulation evaluation method according to claim 1, characterized in that: When performing vibration simulation on the finite element simulation model, the simulation evaluation method further includes: Calculating the stress value of each node in the heat shield based on the frequency response simulation result; When there are nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold, the structure and position of the heat insulation cover are adjusted, and the step of performing vibration simulation on the finite element simulation model is returned to be executed until there are no nodes in the heat insulation cover whose stress values ​​are greater than or equal to the stress value threshold.

5. The simulation evaluation method according to claim 1, characterized in that: The calculation of the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part includes: For each bolt, the first tangential force component and the second tangential force component of the bolt along the tangent plane direction are calculated by vibration simulation; Calculating a tangential resultant force of the bolt based on the first tangential force component and the second tangential force component; Calculating the friction force of the bolt transmitting the transverse load on the section based on the friction coefficient between the bolt and the heat shield, the pre-tightening force of the bolt, and the discreteness of the bolt; The ratio between the tangential resultant force and the friction force is taken as the slip safety factor corresponding to the bolt.

6. The simulation evaluation method according to claim 1, characterized in that: After calculating the sliding safety factor corresponding to each bolt disposed on the heat shield of the automotive power part, the simulation evaluation method further includes: For each bolt, when the slip safety factor corresponding to the bolt does not reach the safety factor threshold, the model and torque range of the target bolt installed at the preset point where the bolt is located are determined based on the support reaction force received by the bolt.

7. A simulation evaluation device for a heat shield in an automobile powertrain, characterized in that: The simulation evaluation device comprises: A model building module, used to build a finite element simulation model of an automobile powertrain system; wherein the finite element simulation model includes a plurality of automobile power parts, each of which is provided with a heat shield, and bolts are provided at preset points of each heat shield; An excitation applying module, used for applying a corresponding vibration excitation load to each automotive power part according to the type of the automotive power part; The safety factor calculation module is used to perform vibration simulation on the finite element simulation model and calculate the sliding safety factor corresponding to each bolt arranged on the heat shield of the automotive power part. When the sliding safety factor corresponding to each bolt reaches the safety factor threshold, it is considered that the heat shield of the automotive power part meets the design requirements.

8. The simulation evaluation device according to claim 7, characterized in that: The vibration excitation load includes engine vibration excitation, road surface non-periodic vibration excitation and motor rotor periodic rotation excitation; when the excitation applying module is used to apply the corresponding vibration excitation load to the automotive power part according to the type of the automotive power part, the excitation applying module is also used to: When the automobile power part is a range extender, applying the engine vibration excitation to the automobile power part; When the automobile power part is a driving motor, the road surface non-periodic vibration excitation and the motor rotor periodic rotation excitation are applied to the automobile power part.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are run by the processor, the steps of the simulation evaluation method for the heat shield in the automotive powertrain as described in any one of claims 1 to 6 are executed.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the simulation evaluation method for a heat shield in an automobile powertrain as claimed in any one of claims 1 to 6 are executed.

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