Connection optimization device and method for improving the robustness of an oil sump and a cylinder block

Abstract

The application provides a connecting optimization device and method for improving the stability of an oil pan and a cylinder body, relates to the technical field of process optimization, and comprises the following modules: a construction module for constructing a connecting action demand model; an identification module for reading vibration and thermal load evolution characteristics under an engine operating state and identifying a stability dominant region set under multiple working conditions; a generation module for generating a connecting point space layout scheme; a coupling state construction module for respectively constructing a connecting coupling state model; an evaluation module for applying a multiple working condition operation excitation to the connecting coupling state model and constructing a connecting stability evaluation tensor; and a configuration module for configuring a target layout scheme. The application solves the technical problem of poor connecting stability of an oil pan and a cylinder body under multiple working conditions caused by the mismatch between local structure stiffness and dynamic load demand in the prior art, and improves the connecting stability by identifying a stability dominant region and optimizing a connecting point layout.

Description

Technical Field

[0001] This application relates to the field of process optimization technology, specifically to a connection optimization device and method for improving the stability of the oil pan and cylinder block. Background Technology

[0002] In traditional oil pan and cylinder block connection designs, bolts, welding, or gaskets are typically used for fixing, relying mainly on historical design experience and static sealing requirements, supplemented by simplified mechanical analysis for layout determination. However, these methods fail to fully consider the complex mechanical requirements of the engine under different operating conditions, especially the matching problem between local structural stiffness and dynamic loads. When the engine operates under variable conditions such as high temperature, high pressure, and vibration, the bolt layout in the oil pan and cylinder block connection area fails to fully consider the local stiffness differences caused by the oil pan's own topology, nor does it couple the complex multi-condition vibration spectrum and thermal load evolution characteristics of the engine during actual operation. This leads to a mismatch between local structural stiffness and dynamic load requirements, thereby weakening the dynamic stability of the connection and affecting the long-term stability and reliability of the engine.

[0003] In summary, the existing technology has a technical problem: due to the mismatch between the local structural stiffness and the dynamic load requirements, the connection stability between the oil pan and the cylinder block is poor under multiple operating conditions, which further affects the long-term stability of the engine. Summary of the Invention

[0004] The purpose of this application is to provide a connection optimization device and method for improving the stability of the oil pan and cylinder block, in order to solve the technical problem in the prior art that the connection stability between the oil pan and cylinder block is poor under multiple operating conditions due to the mismatch between the local structural stiffness and dynamic load requirements, which further affects the long-term stability of the engine.

[0005] To achieve the above objectives, this application provides a connection optimization device and method for improving the stability of the oil pan and cylinder block.

[0006] Firstly, this application provides a connection optimization device for improving the stability of the oil pan and cylinder block. The device includes: a construction module for constructing a connection action demand model based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block, describing the force transmission requirements and constraint relationships between them, wherein the connection action demand model characterizes the distribution of support demand intensity for connection stability in different regions; and an identification module for using the connection action demand model to identify, after reading the vibration and thermal load evolution characteristics under engine operating conditions, the connection action demand model in multi-tasking applications. The system is divided into several modules: a set of stability-dominant regions where the overall stability contribution exceeds a preset threshold under certain conditions; a generation module for generating connection point spatial layout schemes within these stability-dominant regions using connection point layout generation rules; a coupling state construction module for constructing corresponding oil pan-cylinder block-connection point connection coupling state models based on the connection point spatial layout schemes; an evaluation module for applying multi-condition operating excitations to the connection coupling state models and constructing a connection stability evaluation tensor based on displacement response, stress distribution, and relative interface slippage trend; and a configuration module for configuring target layout schemes according to the connection stability evaluation tensor.

[0007] Optionally, the stability analysis region division unit is used to divide the connection area between the oil pan and the cylinder block into multiple stability analysis sub-regions based on the connection action demand model; the region-level contribution feature extraction unit is used to extract the region-level contribution features that affect the overall connection stability for each stability analysis sub-region under multiple operating conditions, wherein the region-level contribution features include region stiffness contribution features, load transfer participation contribution features, and vibration response sensitivity features; the contribution consistency analysis unit is used to perform consistency analysis on the region-level contribution features obtained under different operating conditions for the same stability analysis sub-region, wherein the consistency analysis is used to identify regions that continuously and significantly affect the overall stability under multiple operating conditions, and to reduce the interference of regions that are momentarily prominent under individual operating conditions on the identification results; the evaluation value screening unit is used to determine the stability contribution evaluation value corresponding to the workpiece in each stability analysis sub-region using the consistency analysis results, and constructs the stability analysis sub-regions that are higher than a preset threshold as a set of stability-dominant regions.

[0008] Optionally, the rule constraint unit is used to construct connection point layout generation rules for constraining the spatial distribution of connection points based on the stability-dominant region, wherein the connection point layout generation rules include at least one of the following: a: Force transmission coverage rule, used to constrain the minimum coverage density of connection points in the corresponding support requirement area according to the support requirement intensity distribution of different areas in the connection action requirement model; b: Layout dispersion constraint rule, used to set upper and lower limit thresholds for the spatial distance between adjacent connection points to suppress local stiffness imbalance caused by the concentration or sparseness of connection points; c: Force transmission path balancing rule, used to constrain the contribution weight distribution of different connection points in the overall force transmission network based on the degree of influence of connection points on the load transmission path between the oil pan and the cylinder block, so that the load is distributed along multiple paths; d: Operating condition sensitive adjustment rule, used to dynamically adjust the layout priority of connection points in different stability-dominant areas based on the vibration and thermal load evolution characteristics.

[0009] Optionally, the index construction unit is used to construct a layout difference evaluation index to characterize the degree of structural difference between layout schemes based on the spatial distribution characteristics of connection points and the force transmission path organization characteristics corresponding to each connection point spatial layout scheme. The layout difference evaluation index includes the difference in the distribution of connection point locations and the difference in the coverage of force transmission paths. The difference comparison unit is used to trigger an adaptive adjustment of at least one rule parameter in the connection point layout generation rule when the layout difference evaluation index between any newly generated connection point spatial layout scheme and the existing connection point spatial layout scheme is lower than a preset difference threshold.

[0010] Optionally, the relationship mapping unit is used to uniformly map the geometric positional relationships, assembly constraint relationships, and connection topology relationships of the oil pan, cylinder block, and each connection point according to the connection point spatial layout scheme, forming a structural relationship sub-model describing the spatial association and constraint conditions between the oil pan, cylinder block, and connection points; the characteristic introduction unit is used to introduce corresponding connection stiffness characteristics, connection preload states, and load transfer characteristics to each connection point on the structural relationship sub-model, forming a connection action sub-model characterizing the mechanical coupling behavior of the connection points between the oil pan and cylinder block; the connection coupling state model establishment unit is used to couple and fuse the structural relationship sub-model and the connection action sub-model to establish a connection coupling state model.

[0011] Optionally, the feature extraction unit is used to extract features from the displacement response data, stress distribution data, and interface relative slip trend data obtained under multi-condition operating excitation, and to map the extracted response features to a unified numerical space according to a preset scaling rule; the feature association unit is used to divide the connection area into multiple spatial association units based on the topological structure of the connection area between the oil pan and the cylinder block, and to aggregate the corresponding unique response features, stress distribution features, and interface relative slip trend features in each spatial association unit to form a unit-level multi-feature response vector; the evaluation tensor construction unit is used to map the unit-level multi-feature response vector to different feature dimensions of the tensor according to the response type, using the spatial association unit as the basic index dimension, to construct a connection stability evaluation tensor containing spatial dimension, response type dimension, and operating condition dimension, wherein the combination of different dimensions is used to characterize the joint distribution state of connection stability under different spatial locations, different physical responses, and different operating conditions.

[0012] Optionally, the failure sensitivity analysis unit is used to perform failure sensitivity analysis on each connection point using the connection coupling state model and generate sensitivity indices for the corresponding connection points; the target layout scheme optimization management unit is used to perform target layout scheme optimization management based on the sensitivity indices.

[0013] Optionally, the sampling monitoring module is used to perform sampling verification based on the target layout scheme, execute sampling verification monitoring, generate monitoring feedback, and perform scheme self-optimization management of the target layout scheme based on the monitoring feedback.

[0014] Optionally, the storage module is used to package and store the connection point spatial layout scheme, and to call the packaged storage result according to the monitoring feedback to perform scheme self-optimization management.

[0015] Secondly, this application also provides a connection optimization method for improving the stability of the oil pan and cylinder block. The method includes: constructing a connection action demand model based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block to describe the force transmission requirements and constraint relationships between them. This connection action demand model characterizes the distribution of support demand intensity for connection stability in different regions. Using the connection action demand model, after reading the vibration and thermal load evolution characteristics under engine operating conditions, a set of stability-dominant regions whose overall stability contribution exceeds a preset threshold under multiple operating conditions is identified. A connection point spatial layout scheme is generated within the stability-dominant regions using connection point layout generation rules. Corresponding oil pan-cylinder-connection point connection coupling state models are constructed based on the connection point spatial layout schemes. Multi-operating condition excitations are applied to the connection coupling state models, and a connection stability evaluation tensor is constructed based on displacement response, stress distribution, and interface relative slippage trend. A target layout scheme is configured according to the connection stability evaluation tensor.

[0016] One or more technical solutions provided in this application have at least the following technical effects or advantages: The system employs a construction module to build a connection requirement model based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block. This model describes the force transmission requirements and constraint relationships between the oil pan and cylinder block, and characterizes the distribution of support requirements for connection stability in different regions. An identification module, using the connection requirement model, identifies a set of stability-dominant regions where the overall stability contribution exceeds a preset threshold under multiple operating conditions, after reading the vibration and thermal load evolution characteristics of the engine during operation. A generation module generates spatial layout schemes for connection points within these stability-dominant regions using connection point layout generation rules. A coupling state construction module constructs corresponding oil pan-cylinder block-connection point connection coupling state models based on the connection point spatial layout schemes. An evaluation module applies multi-condition operating excitations to the connection coupling state models and constructs a connection stability evaluation tensor based on displacement response, stress distribution, and relative interface slippage trends. A configuration module configures the target layout scheme according to the connection stability evaluation tensor. In other words, by constructing a connection requirement model, the mechanical requirements and constraint relationships of the connection between the oil pan and the cylinder block in different regions are accurately described. The vibration and thermal load evolution characteristics of the engine are read, the stability-dominant region is identified under multiple operating conditions, and a reasonable connection point spatial layout scheme is generated. By applying multi-condition excitation and combining factors such as displacement response, stress distribution, and relative interface slippage, the connection stability is comprehensively evaluated, the local structural stiffness and connection design are optimized, and long-term stability under various loads and operating conditions is ensured, thereby improving the connection stability between the oil pan and the cylinder block, and thus enhancing the stability of the engine.

[0017] The above description is merely an overview of the technical solution of this application. To better understand the technical means of this application and to facilitate its implementation according to the description, and to make the above and other objects, features, and advantages of this application more apparent, specific embodiments of this application are described below. It should be understood that the content described in this section is not intended to identify key or important features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent through the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the connection optimization device used in this application to improve the stability of the oil pan and cylinder block.

[0020] Figure 2 This is a schematic flowchart of the connection optimization method for improving the stability of the oil pan and cylinder block used in this application.

[0021] Figure labeling: Construction module 11, Identification module 12, Generation module 13, Coupled state construction module 14, Evaluation module 15, Configuration module 16. Detailed Implementation

[0022] This application provides a connection optimization device and method for improving the stability of the oil pan and cylinder block, solving the technical problem in the prior art where the mismatch between local structural stiffness and dynamic load requirements leads to poor connection stability between the oil pan and cylinder block under multiple operating conditions, further affecting the long-term stability of the engine. By constructing a connection action requirement model, the mechanical requirements and constraint relationships of the connection between the oil pan and cylinder block in different regions are accurately described. The vibration and thermal load evolution characteristics of the engine are read, and the stability-dominant region is identified under multiple operating conditions. A reasonable spatial layout scheme for the connection points is generated. By applying multi-condition excitation and combining factors such as displacement response, stress distribution, and relative interface slippage, the connection stability is comprehensively evaluated, optimizing the local structural stiffness and connection design to ensure long-term stability under various loads and operating conditions, thereby improving the connection stability between the oil pan and cylinder block and ultimately enhancing the engine's stability.

[0023] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. It should be understood that this application is not limited to the exemplary embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. It should also be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, not all of them.

[0024] Example 1, please refer to the appendix. Figure 1 This application provides a connection optimization device for improving the stability of the oil pan and cylinder block, wherein the connection optimization device for improving the stability of the oil pan and cylinder block is used to implement the step of the connection optimization method for improving the stability of the oil pan and cylinder block, and the connection optimization device for improving the stability of the oil pan and cylinder block includes: Module 11 is used to construct a connection action demand model based on the topology, material properties and assembly boundary conditions of the oil pan and cylinder block to describe the force transmission demand and constraint relationship between the oil pan and cylinder block. The connection action demand model is used to characterize the distribution of support demand intensity for connection stability in different regions.

[0025] Specifically, based on the topology of the oil pan and cylinder block, the physical properties of the materials, such as elastic modulus and compressive strength, are input to evaluate the stiffness and strength of each component. Load transfer path analysis is performed based on the engine's load under different operating conditions. Through finite element analysis, the force distribution in the connection area between the oil pan and cylinder block under different operating conditions is determined. In other words, a three-dimensional finite element model is constructed based on the geometry and assembly boundary conditions of the oil pan and cylinder block. In finite element modeling, the oil pan, cylinder block, and their connection points are divided into multiple small elements as discrete computational objects. Load information under different operating conditions is input, such as vibration frequency, amplitude, engine operating temperature, and internal combustion pressure. Furthermore, boundary conditions include connection constraints between the oil pan and cylinder block, such as bolted connections and welding.

[0026] Finite element method (FEM) software is used to calculate the stress, displacement, and temperature changes of each element, including static stress analysis, dynamic vibration analysis, and thermo-mechanical coupling analysis. Based on the FEM results, the load transmission path under different operating conditions is analyzed. Specifically, the mechanical behavior of different connection areas, such as bolted connections and the contact surface between the front of the oil pan and the cylinder block, under different load conditions is analyzed to determine which areas have concentrated load transmission and which areas may have the risk of stress concentration or imbalance. Based on the force transmission analysis results, the required strength of connection stability support for different areas is calculated, determining the required support strength for different areas when bearing different loads.

[0027] The topological structure of the oil pan and cylinder block refers to the three-dimensional geometry and spatial composition of the joint between them. This includes not only dimensions but also the connection characteristics, such as which parts are flat, which have reinforced sidewalls, and which have rounded corners. Material properties are the mechanical parameters of the materials constituting the oil pan and cylinder block, such as elastic modulus and Poisson's ratio. For example, cylinder blocks are commonly made of cast iron with an elastic modulus of approximately 110 to 130 GPa; oil pans are commonly made of aluminum alloy with an elastic modulus of approximately 70 GPa. Assembly boundary conditions are the conditions under which components are mutually constrained and fixed during assembly, affecting the relative positions of components and stress transmission paths. For example, the cylinder block is tightly fixed to the crankcase via cylinder head bolts; this contact surface can be considered a fixed constraint. The oil pan, however, is free before assembly.

[0028] The core logic of constructing the connection action demand model lies in the fact that reverse diagnosis does not directly look at stress, but focuses on observing the normal separation trend and tangential slippage trend of the oil pan flange relative to the cylinder block mating surface. Those areas exhibiting significant separation or slippage trends are precisely those areas with insufficient structural stiffness that urgently require external connection points to hold them in place. By quantifying the magnitude of the normal separation trend and tangential slippage trend and normalizing them to a 0-1 range, a connection action demand model characterizing the distribution of support demand intensity is obtained.

[0029] The connection requirement model transforms the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block into a demand heat map covering the entire mating surface. The value at each point in the map represents the magnitude of the support force or constraint stiffness required at that location to maintain the structural stability under base loads. Areas with high values ​​indicate that the structure itself is soft or bears a heavy load transmission burden, thus exhibiting a strong dependence on the connection point. The connection requirement model can characterize the distribution of support strength required in different regions when transmitting loads, determining which regions require more connection support.

[0030] By analyzing the force transmission paths and stress distribution in different regions, areas subjected to high stress can be specifically reinforced to improve the stability of the connection. Load transfer path analysis can help reduce stress concentration and the risk of fatigue damage, thereby improving the long-term stability of the oil pan-cylinder block connection. Prioritizing analysis can help identify potential design problems early, avoiding unnecessary rework during later manufacturing processes and saving costs and time.

[0031] The identification module 12 is used to identify the set of stability-dominant regions whose overall stability contribution is higher than a preset threshold under multiple operating conditions after reading the vibration and thermal load evolution characteristics of the engine under the connected action demand model.

[0032] Furthermore, the identification module 12 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: a stability analysis region division unit, used to divide the connection region between the oil pan and cylinder block into multiple stability analysis sub-regions based on the connection action requirement model; a region-level contribution feature extraction unit, used to extract region-level contribution features that affect the overall connection stability for each stability analysis sub-region under multiple operating conditions, the region-level contribution features including region stiffness contribution features, load transfer participation contribution features, and vibration response sensitivity features; a contribution consistency analysis unit, used to perform consistency analysis on the region-level contribution features obtained under different operating conditions for the same stability analysis sub-region, the consistency analysis is used to identify regions that continuously have a significant impact on the overall stability under multiple operating conditions, and reduce the interference of regions that are momentarily prominent under individual operating conditions on the identification results; and an evaluation value screening unit, used to determine the stability contribution evaluation value corresponding to the workpiece in each stability analysis sub-region using the consistency analysis results, and constructing the stability analysis sub-regions with values ​​higher than a preset threshold as a set of stability-dominant regions.

[0033] Specifically, the multi-condition load spectrum of the engine, obtained beforehand through bench testing, is read. Vibration and thermal load evolution characteristics are a quantitative description of the dynamic loads acting on the oil pan-cylinder block connection system under typical engine operating conditions. Vibration characteristics are typically expressed as vibration power spectral density, describing the distribution of excitation energy with frequency at different engine speeds. For example, at 3000 rpm, significant vibration peaks may exist at 50 Hz, 100 Hz, and 150 Hz, with acceleration amplitudes reaching 15g, 8g, and 5g, respectively, where g is the acceleration due to gravity. Thermal load evolution characteristics are time-varying data of the non-uniform temperature field across the entire component during the engine's transition from cold start to stable full-load operation.

[0034] Based on the connection demand model, the connection area between the oil pan and the cylinder block is divided according to the natural boundaries of demand intensity, automatically dividing the entire connection interface into multiple stability analysis sub-regions. The division of these stability analysis sub-regions is based not only on geometric location but also on the gradient change of demand intensity. For example, a high demand intensity region and its adjacent transition zone are classified as a sub-region, ensuring that each sub-region has relatively consistent mechanical properties.

[0035] For each stability analysis sub-region, transient dynamic analysis or frequency response analysis coupled with thermal stress was performed under multi-condition operation, and regional contribution characteristics were extracted, including regional stiffness contribution characteristics, load transfer participation contribution characteristics, and vibration response sensitivity characteristics. The regional stiffness contribution characteristic is usually measured by the proportion of the sub-region in the overall structural modal strain energy. The higher the proportion, the greater the impact of changing the stiffness of this region on the overall dynamic characteristics. For example, a certain sidewall sub-region contributed 25% of the strain energy in the first torsional mode. The load transfer participation contribution characteristic is the proportion of the shear force or normal force transferred by the connection point in this region to the total interface force. The higher the proportion, the more critical the region is in the force transmission path. The vibration response sensitivity characteristic is the peak value of the maximum normal separation displacement or tangential slip velocity of the oil pan relative to the cylinder block in this sub-region under foundation vibration excitation. For example, under 50Hz excitation, the maximum separation displacement of a certain corner sub-region reached 0.05mm.

[0036] For the same stability analysis sub-region, its regional contribution characteristics under different operating conditions are calculated, namely, regional stiffness contribution characteristics, load transfer participation contribution characteristics, and vibration response sensitivity characteristics. A consistency analysis is then performed on these characteristics to compare the contribution features of the same region under different operating conditions, identifying which regions significantly affect overall stability in all conditions. This consistency analysis reduces the interference of single operating conditions on stability contribution results, yielding more robust stability-dominant regions. For example, suppose a sub-region X located on the front side of the oil pan has maximum separation displacements of 0.02 mm in condition A, 0.18 mm in condition B, 0.20 mm in condition C, and 0.05 mm in condition D, with a mean of 0.1125 mm but a large standard deviation, indicating that it is only sensitive under conditions B and C, and insensitive at idle speed. The other sub-region, Y, located in the middle of the sidewall, exhibited displacements of 0.10 mm, 0.12 mm, 0.15 mm, and 0.11 mm under four operating conditions, with a mean of 0.12 mm and a very small standard deviation, indicating that it consistently demonstrated high sensitivity under all operating conditions. Clearly, the consistency of sub-region Y is far superior to that of sub-region X.

[0037] Based on the stiffness contribution characteristics, load transfer participation contribution characteristics, and vibration response sensitivity characteristics of each stability analysis sub-region, the stability contribution evaluation value of that region is calculated, quantifying its contribution to overall stability under various working conditions. Weights are assigned to each feature; for example, considering the primary goal of preventing bolt loosening and leakage, the weight of the vibration response sensitivity feature might be set to 0.5, the load transfer participation feature to 0.3, and the region stiffness contribution feature to 0.2. A comprehensive score is given to each sub-region. The scoring formula considers not only the mean of the feature values ​​but also their coefficients of variation. The mean represents the magnitude of influence, while the coefficient of variation represents consistency; typically, lower coefficients of variation receive a positive bonus. The coefficients of variation for each feature value are obtained using conventional calculation formulas. The stability contribution evaluation value is calculated as follows: (0.5 * normalized mean vibration sensitivity * (1 - vibration coefficient of variation)) + (0.3 * normalized mean load participation * (1 - participation coefficient of variation)) + (0.2 * normalized mean stiffness contribution). The scores for all sub-regions are normalized to the 0-1 range using the maximum-minimum method. In sub-region P1, the average stiffness contribution is 20%, the average load transfer participation is 20%, and the average vibration response sensitivity is 0.120 mm. In sub-region P2, the average stiffness contribution is 17%, the average load transfer participation is 19%, and the average vibration response sensitivity is 0.123 mm. In sub-region P3, the average stiffness contribution is 6.5%, the average load transfer participation is 7.5%, and the average vibration response sensitivity is 0.113 mm. For sub-region P1, its vibration sensitivity is very stable across the four operating conditions, with a calculated coefficient of variation of 0.15. The coefficient of variation for load participation is 0.15, and the coefficient of variation for stiffness contribution is 0.10. For sub-region P2, the coefficient of variation for vibration sensitivity is 0.22, the coefficient of variation for load participation is 0.16, and the coefficient of variation for stiffness contribution is 0.12. For sub-region P3, its vibration sensitivity fluctuates greatly under the four working conditions, with a calculated coefficient of variation as high as 0.70. Its coefficient of variation for load participation is 0.20, and the coefficient of variation for stiffness contribution is 0.23, indicating that this region is only vulnerable under certain working conditions and is not continuously critical. A weighted synthesis algorithm is used to combine the average value and consistency, and the final calculation results are normalized to obtain the final stability contribution evaluation value. According to the aforementioned formula, the stability contribution evaluation value for sub-region P1 is 0.92, the stability contribution evaluation value for sub-region P2 is 0.88, and the stability contribution evaluation value for sub-region P3 is 0.58. The contribution scores of all sub-regions were ranked, and based on the design strategy of focusing on the top 30%, a preset threshold of 0.74 was set. All sub-regions with scores higher than this threshold were selected. Therefore, regions P1 and P2 were both selected, forming a stable dominant region set. Sub-region P3, due to its extremely poor consistency, had a comprehensive score of only 0.58 and was effectively excluded from the dominant set.

[0038] A preset threshold is set based on design constraints to filter out the most critical parts from all sub-regions. The threshold can be set based on proportion or absolute score, and its setting needs to balance the design goals: too high a threshold may cause critical areas to be missed, while too low a threshold will make the dominant set too large and lose the optimization focus.

[0039] The stability contribution evaluation value of each stability analysis sub-region is compared with a preset threshold. All stability analysis sub-regions with scores exceeding the preset threshold have their numbers and geometric information automatically extracted, forming the final set of dominant stability regions. This set of dominant stability regions clearly indicates which areas should be prioritized and emphasized with limited design resources, focusing on enhancing the connectivity, material selection, or arrangement of connection points in these areas.

[0040] By refining the analysis into multiple stability sub-regions, we can accurately identify which regions have a significant impact on connection stability under different operating conditions, avoiding overly coarse overall analysis. Through consistency analysis, we can identify which regions consistently and significantly affect stability under multiple operating conditions, and focus on optimizing the connection design of these dominant regions to ensure connection stability.

[0041] The generation module 13 is used to generate a spatial layout scheme of connection points within the stable dominant region using connection point layout generation rules.

[0042] Furthermore, the generation module 13 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: a rule constraint unit, used to construct connection point layout generation rules for constraining the spatial distribution of connection points based on the stability dominant region, wherein the connection point layout generation rules include at least one of the following: a: Force transmission coverage rule, used to constrain the minimum coverage density of connection points in the corresponding support requirement area according to the support requirement intensity distribution of different areas in the connection action requirement model; b: Layout dispersion constraint rule, used to set upper and lower limit thresholds for the spatial distance between adjacent connection points to suppress local stiffness imbalance caused by the concentration or sparseness of connection points; c: Force transmission path balancing rule, used to constrain the contribution weight distribution of different connection points in the overall force transmission network based on the degree of influence of connection points on the load transmission path between the oil pan and the cylinder block, so that the load is distributed along multiple paths; d: Operating condition sensitive adjustment rule, used to dynamically adjust the layout priority of connection points in different stability-dominant areas based on the vibration and thermal load evolution characteristics.

[0043] Specifically, based on the identified stability-dominant region in the connection between the oil pan and the cylinder block, connection point layout generation rules are constructed, including multiple sub-rules. The aim is to ensure that the arrangement of connection points meets both mechanical requirements and engineering feasibility. These connection point layout generation rules include at least force transmission coverage rules, layout dispersion constraint rules, force transmission path balancing rules, and operating condition-sensitive adjustment rules. In essence, these rules stipulate that the spatial arrangement of connection points in the oil pan and cylinder block connection design must meet specific mechanical requirements to ensure the stability of the connection.

[0044] The force transmission coverage rule is used to constrain the minimum coverage density of connection points within the corresponding support requirement area based on the support requirement intensity distribution of different regions in the connection action requirement model. Ensuring sufficient density of connection points in areas with high stress enhances the stability of these areas. Within stability-dominant regions, the density of connection points is constrained according to the support requirement intensity distribution provided in the connection action requirement model. Areas with high support requirement should have more connection points, while areas with low support requirement can have fewer connection points.

[0045] The purpose of layout dispersion constraints is to prevent connection points from being too concentrated or too sparse in space. Excessive concentration can lead to local stiffness imbalance, while excessive sparseness may prevent effective load transfer. By setting upper and lower thresholds for the distance between adjacent connection points, a reasonable distribution of connection points is ensured. Constraining the spatial distance between adjacent connection points by setting certain upper and lower thresholds avoids excessive concentration or dispersion. For example, assuming the distance between connection points cannot be less than 10mm or greater than 50mm, this prevents local stiffness imbalance caused by excessive concentration and ineffective load transfer due to excessive sparseness.

[0046] The load transmission path balancing rule ensures a balanced load transmission path between the oil pan and cylinder block by rationally arranging connection points. By adjusting the weight distribution of different connection points in load transmission, it avoids concentrated load transmission to a single path, ensuring that the load is evenly distributed across multiple paths and reducing localized stress concentration. During the connection point layout generation process, it is crucial to ensure that the load transmission path is balanced. Adjusting the arrangement of connection points allows the load to be transmitted through multiple paths, rather than concentrating on a single path.

[0047] Considering that the engine will experience different operating conditions during operation, the condition-sensitive adjustment rule dynamically adjusts the layout priority of connection points in different stability-dominant regions based on the evolution characteristics of vibration and thermal load. Specifically, under certain operating conditions, specific areas may bear higher thermal or vibration loads, and the priority of connection point placement should be concentrated in these areas.

[0048] Based on the vibration and thermal load characteristics under different operating conditions, the priority of the connection point layout is dynamically adjusted. For example, under high temperature and high pressure conditions, the contact area between the oil pan and the cylinder block may bear more thermal load, and the connection point layout should be concentrated in these areas; while under low temperature and low pressure conditions, the connection point density in these areas can be appropriately reduced.

[0049] Furthermore, the generation module 13 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: an index construction unit, used for constructing a layout difference evaluation index to characterize the degree of structural difference between layout schemes based on the spatial distribution characteristics and force transmission path organization characteristics of the connection points corresponding to each connection point spatial layout scheme, the layout difference evaluation index including the difference in the distribution of connection point positions and the difference in the coverage of force transmission paths; and a difference comparison unit, used for triggering an adaptive adjustment of at least one rule parameter in the connection point layout generation rules when the layout difference evaluation index between any newly generated connection point spatial layout scheme and the existing connection point spatial layout scheme is lower than a preset difference threshold.

[0050] Specifically, based on the distribution of support intensity requirements and other design requirements within the stability-dominant region, connection point layout generation rules are applied to generate a spatial layout scheme for connection points. This spatial layout scheme determines the specific spatial distribution of connection points according to the connection point layout generation rules, ensuring that within the stability-dominant region, the arrangement of connection points can meet the support intensity requirements and load transfer requirements of different areas.

[0051] For each generated connection point spatial layout scheme, its connection point spatial distribution characteristics and force transmission path organization characteristics are analyzed. The connection point spatial distribution characteristics are a set describing the geometric arrangement of all connection points in two-dimensional or three-dimensional space within a layout scheme. Key features include: the total number of connection points, the coordinate set of each point, the distance matrix between points, and a spatial distribution uniformity index calculated based on the point set, quantifying the geometric morphology of the layout. The force transmission path organization characteristics describe the route of load transmission between the oil pan and cylinder block under a specific layout, including the number of main force transmission paths, path lengths, angles between paths, and network robustness indicators, quantifying the mechanical topology of the layout.

[0052] The evaluation index for calculating the degree of structural differences between layout schemes includes the difference in the distribution of connection points and the difference in the coverage of load transmission paths. The difference in the distribution of connection points quantifies the degree of similarity between two layout schemes in geometric space. Simply put, it calculates the average of the minimum geometric deviation required to move the point set of one layout to be as close as possible to the point set of another layout. The higher the difference value, the less similar the two layouts are in spatial location. The difference in the coverage of load transmission paths quantifies the degree of similarity between two layout schemes in mechanical function. It compares the load transmission path organization characteristics of the two layouts. If the main loads of both layouts are transmitted along the exact same few lines, then their path coverage difference is low; conversely, if the load transmission route networks are completely different, the difference is high.

[0053] The newly generated connection point spatial layout scheme is compared with existing layout schemes, and a layout difference evaluation index is calculated between them. If the difference index between the new scheme and the existing scheme is lower than a preset threshold, the two layout schemes are considered to have small structural differences. The preset difference threshold serves as the boundary for measuring the structural differences between connection point spatial layout schemes. If the difference index between the newly generated layout scheme and the existing scheme is lower than this threshold, the new scheme is considered to be an approximate repetition of the existing scheme, lacking novelty, and the strategy needs to be adjusted. When a new scheme is detected to be too similar to an old scheme, key parameters in the layout generation rules are automatically modified to guide the algorithm to explore new design spaces. This adjustment is not random but targeted, such as temporarily increasing or decreasing the minimum density requirement for that area, or relaxing the upper and lower limits of spacing in the layout dispersion constraint rules.

[0054] For example, based on the connection point layout generation rules within the stability-dominant region, a connection point spatial layout scheme, denoted as Scheme A, is generated using a genetic optimization algorithm. Scheme A is then rapidly analyzed to extract two main features: spatial distribution characteristics (calculating the coordinate matrix and distance distribution histogram of all bolts) and force transmission path organization characteristics (identifying 3-4 main load transmission paths through a simplified linear statics analysis or network flow analysis, and recording the bolt number sequence and load proportion borne by each path). Scheme A is stored in a scheme library. When the genetic algorithm iteratively generates a new Scheme B, its features are similarly extracted, and then its differences are compared with all existing schemes in the scheme library. The average minimum corresponding point distance method is used. For each bolt in Scheme B, the bolt with the closest Euclidean distance in Scheme A is found, and this distance is recorded. Then, the average of all such distances is taken. Similarly, Scheme B is calculated again using Scheme A as a benchmark, and the larger of the two averages is taken. Finally, divide this value by a characteristic length, such as the average flange width of 50 mm, and normalize it, assuming a value of 0.65. Compare the main force transmission paths of the two schemes. Assume that scheme A has 3 main paths and scheme B has 3 main paths. Calculate the spatial coverage similarity of each path, such as determining whether the bolt positions passed by the path overlap by more than 70%. If the overlap between the path of scheme B and any path of scheme A is less than 50%, the path is considered novel. Through weighted calculation, a path difference score is obtained, assuming a score of 0.70. Set a comprehensive difference threshold, such as 0.60. The comprehensive difference of scheme B relative to scheme A, such as the geometric mean of the two differences, is sqrt(0.65*0.70). Since 0.67 is higher than the threshold of 0.60, scheme B is considered novel and stored in the scheme library. By continuously repeating this process, the optimal connection point spatial layout scheme is finally obtained, ensuring that it meets all design requirements and effectively improves the stability of the connection.

[0055] By comparing the differences in various layout schemes, the spatial layout of connection points is precisely optimized to ensure uniform load transfer in the connection area and avoid stress concentration and localized failure. Adaptive adjustments avoid requiring a complete redesign for each layout scheme, reducing design iterations and improving design efficiency and production cycle time.

[0056] The coupling state construction module 14 is used to construct corresponding oil pan-cylinder-connection point connection coupling state models based on the connection point spatial layout scheme.

[0057] Furthermore, the coupling state construction module 14 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: a relationship mapping unit, used to uniformly map the geometric positional relationship, assembly constraint relationship and connection topology relationship of the oil pan, cylinder block and each connection point according to the connection point spatial layout scheme, forming a structural relationship sub-model describing the spatial association and constraint conditions between the oil pan, cylinder block and connection point; a characteristic introduction unit, used to introduce corresponding connection stiffness characteristics, connection preload state and load transfer characteristics to each connection point on the structural relationship sub-model, forming a connection action sub-model for characterizing the mechanical coupling behavior of the connection point between the oil pan and cylinder block; and a connection coupling state model establishment unit, used to couple and fuse the structural relationship sub-model and the connection action sub-model to establish a connection coupling state model.

[0058] Specifically, based on the spatial layout scheme of the connection points, the geometric positions of the oil pan, cylinder block, and connection points are analyzed, and the assembly constraints and connection topology relationships between them are determined. Geometric positional relationships refer to the spatial positions and interrelationships of the oil pan, cylinder block, and each connection point; assembly constraints refer to the constraints between each connection point and between the oil pan and cylinder block during actual assembly; and connection topology relationships refer to the connection methods and structural characteristics between the oil pan, cylinder block, and connection points. Using the geometric positional relationships, assembly constraints, and connection topology relationships, a structural relationship sub-model is constructed to describe the spatial associations and constraints between the oil pan and cylinder block, and between them and the connection points, as well as the spatial associations and mechanical constraints between each component.

[0059] Based on the structural relationship sub-model, a connection action sub-model is constructed for each connection point, considering connection stiffness characteristics, connection preload, and load transfer characteristics. For each connection point, its stiffness is evaluated based on its material properties, geometry, and assembly method, and the influence of preload on the connection is considered. The method of load transfer through these connection points is analyzed, and the load transfer capacity of each connection point is calculated. Connection stiffness characteristics reflect the connection point's resistance to deformation under external loads; higher stiffness indicates a smaller deformation response to loads, while lower stiffness indicates a more flexible connection. Connection preload refers to whether a certain tightening force has been pre-applied to the connection point during installation. Preload affects the deformation and load transfer efficiency of the connection point; excessive or insufficient preload may lead to an unstable connection or excessive deformation. Load transfer characteristics describe how the connection point transfers the load applied from the oil pan or cylinder block during the connection between the oil pan and the cylinder block, including load distribution, transfer path, and intensity.

[0060] By coupling the structural relationship sub-model with the connection action sub-model, a connection coupling state model is formed. This model integrates structural relationships and mechanical coupling, describing how the connection points respond to load changes under different operating conditions and predicting the stability of the connection. During the coupling process, the stiffness, preload state, and load transfer characteristics of the connection points are combined with the spatial constraints in the structural relationships to form a multi-dimensional mechanical coupling model capable of simulating the stress conditions and stability of the connection. By coupling the structural relationship sub-model and the connection action sub-model, a complete model describing the mechanical interaction between the oil pan, cylinder block, and connection points is formed, reflecting how the connection points respond to loads under different operating conditions and predicting the stability of the entire connection.

[0061] A transient dynamic analysis was performed on the coupled system model by applying a load simulating the lateral vibration of an engine. Based on the simulation results, the model was verified to ensure it could reliably predict the mechanical behavior of the coupled system under dynamic loads. For example, after disassembly, contact marks were observed using a pressure-sensitive membrane. The pressure distribution trend was found to be highly consistent with the pressure cloud map predicted by the simulation, with higher pressure in the sidewall region and lower pressure in the bottom region, and no continuous zero-pressure area. This indicates that the coupled system model is qualified.

[0062] By using a coupled structural relationship sub-model and a connection action sub-model, the mechanical performance of the oil pan and cylinder block connection is accurately displayed, especially its performance under complex operating conditions, allowing for the early identification of potential weaknesses or unstable areas. By analyzing the stiffness, preload, and load transfer characteristics of the connection points, the connection point layout is optimized to ensure uniform load transfer, reduce local stress concentration, and improve overall stability.

[0063] Evaluation module 15 is used to apply multi-condition operating excitation to the connection coupling state model and construct a connection stability evaluation tensor based on displacement response, stress distribution, and interface relative slip trend.

[0064] Furthermore, the evaluation module 15 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: a feature extraction unit, used for extracting features from displacement response data, stress distribution data, and interface relative slip trend data obtained under multi-condition operating excitation, and mapping the extracted response features to a unified numerical space according to a preset scale transformation rule; a feature association unit, used for dividing the connection area into multiple spatial association units based on the topological structure of the connection area between the oil pan and cylinder block, and aggregating the corresponding unique response features, stress distribution features, and interface relative slip trend features in each spatial association unit to form a unit-level multi-feature response vector; and an evaluation tensor construction unit, used for mapping the unit-level multi-feature response vector to different feature dimensions of the tensor according to the response type, using the spatial association unit as the basic index dimension, to construct a connection stability evaluation tensor containing spatial dimension, response type dimension, and operating condition dimension, wherein the combination of different dimensions is used to characterize the joint distribution state of connection stability under different spatial locations, different physical responses, and different operating conditions.

[0065] Specifically, during the design process, multi-condition excitation tests were conducted on the connection between the oil pan and the cylinder block based on actual usage scenarios. These tests included environmental factors such as high temperature, high pressure, and vibration, simulating the load conditions encountered by the connection system in actual operation. Similarly, for multiple connection point spatial layout schemes, the corresponding connection coupling state models could be run for each scheme, and preset multi-condition loads could be applied sequentially. Transient dynamics or thermo-mechanical coupling analysis was performed for each condition, outputting displacement, stress, and contact state time history data for all nodes.

[0066] Data on displacement response, stress distribution, and relative slippage trend of interfaces under various operating conditions are collected. Displacement response data is the dynamic displacement of the oil pan relative to the cylinder block, especially normal separation (affecting sealing) and tangential slippage (affecting fretting wear). Stress distribution data includes the axial stress and shear stress of bolts, flange contact pressure, and equivalent stress of the component body. Relative slippage trend data of interfaces is the ratio of tangential force to normal force on the contact surface, or the directly calculated microscopic slippage displacement, used to evaluate the anti-loosening capability.

[0067] Feature extraction is performed on displacement response data, stress distribution data, and interface relative slip trend data. For example, for displacement response, the maximum normal displacement of each node is calculated; for bolt stress, the stress amplitude of each bolt is extracted; and for interface slip trend, the maximum ratio of tangential force to normal force at each point on the contact surface is calculated. Using scaling rules, these response features are mapped to a unified numerical space, and features with different units and dimensions are converted to the same dimension through standardization and normalization methods.

[0068] Based on the topological structure of the connection area between the oil pan and the cylinder block, the connection area is divided into multiple spatially related units. Each unit contains a certain range of connection points, and the displacement, stress, and slip response characteristics of these connection points are aggregated into a multi-feature response vector at the unit level. The unit-level multi-feature response vector is the set of all eigenvalues ​​of each spatially related unit under a specific operating condition. In other words, the oil pan flange surface is divided into a uniform grid on a two-dimensional plane. For each unit, the normalized value of a certain feature of all nodes falling within that unit is collected. For unfavorable features, the maximum value within that unit is taken, representing the worst-case scenario; for favorable features, the minimum value is taken.

[0069] Multiple spatially correlated units are used as the basic index dimensions, and the multi-feature response vectors in each spatially correlated unit are mapped to different dimensions of the tensor. The spatial dimension represents different locations in the connected region; the response type dimension includes different response features such as displacement, stress, and slip; and the working condition dimension reflects the response changes under different working conditions. The size of the spatial dimension is determined based on the spatial partitioning results. The size of the response type dimension is determined based on the feature extraction scheme. The size of the working condition dimension is determined based on the number of simulated working conditions.

[0070] For each operating condition, post-processing of the simulation results yields the raw data for all nodes. For each spatially associated unit, based on the nodes it contains, each feature value of that unit under each operating condition is extracted. Note that different types of features may use different aggregation methods. The extracted feature values ​​are normalized and mapped to a unified numerical space, such as between 0 and 1, where 0 represents the best and 1 represents the worst. The normalized values ​​are then filled into the connectivity robustness evaluation tensor. The connectivity robustness evaluation tensor is a three-dimensional data structure. The first dimension indexes the spatial units, the second dimension indexes different physical features, and the third dimension indexes different operating conditions, comprehensively representing the robustness characteristics of the connected system under different spatial locations, different physical responses, and different operating conditions. Tensor element T(i,j,k) represents the evaluation value of the j-th feature of the i-th unit under the k-th operating condition, fully encapsulating the performance of the connected system under all conditions.

[0071] By employing multi-condition excitation, the mechanical performance of the oil pan-cylinder block connection is comprehensively evaluated to ensure stable operation under various conditions. A connection stability evaluation tensor is constructed to comprehensively analyze the stability of the connection region, providing a holistic evaluation for different locations, operating conditions, and response types.

[0072] Configuration module 16 is used to configure a target layout scheme based on the connection stability evaluation tensor.

[0073] Furthermore, the configuration module 16 in the connection optimization device for improving the stability of the oil pan and cylinder block is also used for: a failure sensitivity analysis unit, used to perform failure sensitivity analysis on each connection point using the connection coupling state model, and generate sensitivity indices for the corresponding connection points; and a target layout scheme optimization management unit, used to perform target layout scheme optimization management based on the sensitivity indices.

[0074] Specifically, since different features in the tensor have different dimensions, weights are assigned to each feature dimension and operating condition dimension. For each connection point spatial layout scheme, the connection stability evaluation tensor is used for evaluation, identifying the weakest element and its evaluation value, identifying the operating condition under which each scheme performs worst, and analyzing the performance of each scheme across various failure modes. Using a genetic optimization algorithm, based on the data in the connection stability evaluation tensor, the layout of connection points is redistributed to ensure that the density of connection points is increased or their preload is adjusted in critical areas to enhance overall stability. For example, suppose that in the connection stability evaluation tensor, some connection points, such as elements 5 and 7, have stress responses exceeding preset thresholds under high temperature and high pressure conditions, resulting in poor connection stability in that area. In the generation of the target layout scheme, these areas will be given priority, and the arrangement of connection points will be optimized through the algorithm, increasing the density of connection points or appropriately adjusting the preload.

[0075] The target layout scheme not only optimizes the number and location of connection points in different areas, but also considers the stiffness, preload, and load transfer characteristics of the connection points to ensure that the connection system can effectively transfer loads and avoid local instability under multiple operating conditions. Through optimization rules, such as layout dispersion constraints, the spatial distribution of connection points is further adjusted to avoid over-concentration or over-sparseness. The final target layout scheme should consider the stability requirements under all operating conditions, ensuring that the stability of the oil pan and cylinder block connection system is optimized under different operating environments.

[0076] By optimizing the layout of connection points, localized stress concentration or excessive displacement is avoided, thus improving the overall stability of the connection between the oil pan and the cylinder block. By rationally distributing the density of connection points and adjusting their stiffness and preload, the load is ensured to be transmitted evenly, preventing connection instability or loosening.

[0077] Each connection point is analyzed using a connection coupling state model, considering the impact of various operating conditions on the connection points, and the response data of each connection point under different operating conditions, such as displacement, stress, and slippage, are calculated. For example, assuming that the stress of a connection point is 200 MPa under high-temperature conditions and the displacement is 0.5 mm under vibration conditions, the connection coupling state model is used to calculate and evaluate whether the connection point may fail under changing operating conditions.

[0078] Based on the response data of the connection points, a sensitivity index is generated for each connection point through failure sensitivity analysis. The sensitivity index is used to quantify the degree of influence of each connection point on system failure. The higher the sensitivity index, the more likely the connection point is to fail under different operating conditions; conversely, the lower the sensitivity index, the better the stability of the connection point.

[0079] Based on the sensitivity index of each connection point, the target layout scheme is optimized. For connection points with high sensitivity, the connection point density is increased, the connection point positions are adjusted, and the preload state of the connection points is changed. For connection points with high sensitivity, the load distribution at that point is made more uniform by increasing the connection point density or adjusting the connection point layout, thereby reducing the sensitivity of that point. The optimized target layout scheme will be verified for effectiveness through numerical simulation and experiments to ensure that it can maintain the stability of the connection system under different operating conditions. If the optimized scheme does not perform ideally in actual operating conditions, the layout will be further adjusted based on the test results until the ideal connection stability is achieved.

[0080] By optimizing connection points with high failure sensitivity, the stability of the connection between the oil pan and the cylinder block is improved. Sensitivity analysis identifies connection points prone to failure under specific operating conditions, and optimization measures are taken for these points to effectively reduce the risk of failure. Quantifying sensitivity indicators enables more refined connection point layout and design optimization, avoiding over- or under-design issues and ensuring the rational use of resources.

[0081] Furthermore, the connection optimization device for improving the stability of the oil pan and cylinder block also includes: a sampling monitoring module, used to perform sampling verification according to the target layout scheme, perform sampling verification monitoring, generate monitoring feedback, and perform scheme self-optimization management of the target layout scheme based on the monitoring feedback.

[0082] Specifically, the target layout scheme includes the location distribution of connection points, the density of connection points, and the distribution of preload, aiming to improve the connection stability between the oil pan and the cylinder block. Prototype verification is performed based on the target layout scheme. Physical samples are created in actual production, and the performance of the layout scheme under real-world operating conditions is verified through actual testing and monitoring. Prototype verification is a preliminary test of the design scheme, helping to identify potential problems and areas for optimization.

[0083] The prototyping samples are tested and monitored, typically including static and dynamic tests, to obtain the performance of the connection system under actual working conditions, including stress monitoring, displacement monitoring, and slippage monitoring. Based on the monitoring data, a detailed monitoring feedback report is generated, including the actual response data of each connection point, such as stress, displacement, and slippage, to help analyze the performance of the target layout scheme under actual working conditions. Based on the monitoring feedback, the target layout scheme is self-optimized and managed. Specifically, the layout scheme is adjusted through a genetic optimization algorithm, especially for connection points that perform poorly in the feedback, such as those with excessive stress, by adjusting density, increasing preload, or rearranging their positions.

[0084] Based on the results of prototyping and verification monitoring and adjustments made through self-optimization management, a new optimized layout scheme is generated and verified again. This process can be iterated multiple times until the final target layout scheme meets the predetermined stability and reliability requirements. In other words, the target layout scheme is automatically adjusted and optimized based on feedback from prototyping and verification monitoring. Self-optimization management means automatically executing optimization algorithms to modify the scheme based on real-time monitoring data, further improving the performance and adaptability of the target layout scheme.

[0085] Through physical prototyping and monitoring feedback, we can accurately understand the performance of the target layout scheme under actual working conditions. Through self-optimization management, we adjust the target layout scheme based on real-time feedback to ensure that the design can meet the stability requirements to the greatest extent.

[0086] Furthermore, the connection optimization device for improving the stability of the oil pan and cylinder block also includes: a storage module, used to package and store the connection point spatial layout scheme, and to call the packaged storage results according to the monitoring feedback to perform scheme self-optimization management.

[0087] Specifically, during the generation of the target layout scheme, a series of design operations were completed, including the arrangement of connection points, optimization of density, and adjustment of preload. The spatial layout scheme of connection points was packaged into a standardized data format. During the prototyping verification and actual working condition testing, feedback reports were generated by monitoring data such as stress, displacement, and slippage. These reports reflected the actual performance of the current layout scheme, including which areas experienced stress exceeding preset thresholds and which connection points experienced displacement exceeding the design range.

[0088] Based on monitoring feedback reports, the system automatically selects and invokes suitable pre-packaged and stored connection point spatial layout schemes. Adjustments are made based on the feedback, or rapid scheme switching is performed to suit different operating conditions. Automated optimization management is implemented based on the invoked layout scheme and feedback data. Scheme self-optimization management uses intelligent optimization algorithms to dynamically adjust the connection point layout, ensuring that stress, displacement, and other response parameters reach their optimal state. After optimization, the new layout scheme is repackaged and stored, updating the original layout scheme, ensuring that all optimization results are recorded for further optimization.

[0089] By packaging and storing optimized solutions, historical solutions can be quickly retrieved, reducing the workload of recalculation and design and improving the efficiency of the optimization process. Based on real-time monitoring feedback, the layout scheme is dynamically adjusted and optimized to ensure that the design consistently achieves optimal stability and reliability under different operating conditions. Continuously optimizing the target layout scheme effectively improves the long-term reliability and stability of the oil pan-cylinder block connection, reducing the risk of failure caused by unreasonable design.

[0090] In summary, the connection optimization device for improving the stability of the oil pan and cylinder block provided in this application has the following technical effects: The system employs a construction module to build a connection requirement model based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block. This model describes the force transmission requirements and constraint relationships between the oil pan and cylinder block, and characterizes the distribution of support requirements for connection stability in different regions. An identification module, using the connection requirement model, identifies a set of stability-dominant regions where the overall stability contribution exceeds a preset threshold under multiple operating conditions, after reading the vibration and thermal load evolution characteristics of the engine during operation. A generation module generates spatial layout schemes for connection points within these stability-dominant regions using connection point layout generation rules. A coupling state construction module constructs corresponding oil pan-cylinder block-connection point connection coupling state models based on the connection point spatial layout schemes. An evaluation module applies multi-condition operating excitations to the connection coupling state models and constructs a connection stability evaluation tensor based on displacement response, stress distribution, and relative interface slippage trends. A configuration module configures the target layout scheme according to the connection stability evaluation tensor. In other words, by constructing a connection requirement model, the mechanical requirements and constraint relationships of the connection between the oil pan and the cylinder block in different regions are accurately described. The vibration and thermal load evolution characteristics of the engine are read, the stability-dominant region is identified under multiple operating conditions, and a reasonable connection point spatial layout scheme is generated. By applying multi-condition excitation and combining factors such as displacement response, stress distribution, and relative interface slippage, the connection stability is comprehensively evaluated, the local structural stiffness and connection design are optimized, and long-term stability under various loads and operating conditions is ensured, thereby improving the connection stability between the oil pan and the cylinder block, and thus enhancing the stability of the engine.

[0091] Example 2: Based on the same inventive concept as the connection optimization device for improving the stability of the oil pan and cylinder block in Example 1, this application also provides a connection optimization method for improving the stability of the oil pan and cylinder block. Please refer to the appendix. Figure 2 The connection optimization method for improving the stability of the oil pan and cylinder block includes: Based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block, a connection action demand model is constructed to describe the force transmission requirements and constraint relationships between the oil pan and cylinder block. This model characterizes the distribution of support demand intensity for connection stability in different regions. Using this model, after reading the vibration and thermal load evolution characteristics under engine operating conditions, a set of stability-dominant regions with an overall stability contribution exceeding a preset threshold under multiple operating conditions is identified. Connection point layout generation rules are used to generate spatial layout schemes for connection points within these stability-dominant regions. Based on these spatial layout schemes, corresponding oil pan-cylinder-connection point connection coupling state models are constructed. Multi-condition operating excitations are applied to these connection coupling state models, and a connection stability evaluation tensor is constructed based on displacement response, stress distribution, and relative interface slippage trend. A target layout scheme is configured according to the connection stability evaluation tensor.

[0092] Furthermore, the identification of the set of stability-dominant regions whose overall stability contribution exceeds a preset threshold under multiple operating conditions includes: dividing the connection area between the oil pan and the cylinder block into multiple stability analysis sub-regions based on the connection action demand model; for each stability analysis sub-region, extracting regional-level contribution features that affect the overall connection stability under multiple operating conditions, the regional-level contribution features including regional stiffness contribution features, load transfer participation contribution features, and vibration response sensitivity features; for the same stability analysis sub-region, performing consistency analysis on the regional-level contribution features obtained under different operating conditions, the consistency analysis is used to identify regions that continuously and significantly affect the overall stability under multiple operating conditions, and to reduce the interference of regions that are momentarily prominent under individual operating conditions on the identification results; using the consistency analysis results to determine the stability contribution evaluation value corresponding to the workpiece in each stability analysis sub-region, and constructing the stability analysis sub-regions with values ​​exceeding the preset threshold as a set of stability-dominant regions.

[0093] Furthermore, the step of generating a spatial layout scheme for connection points within the stability-dominant region using connection point layout generation rules includes: constructing connection point layout generation rules based on the stability-dominant region to constrain the spatial distribution of connection points. These connection point layout generation rules include at least one of the following: a) a force transmission coverage rule, used to constrain the minimum coverage density of connection points within the corresponding support requirement region based on the support requirement intensity distribution in different regions of the connection action requirement model; b) a layout dispersion constraint rule, used to set upper and lower limit thresholds for the spatial distance between adjacent connection points to suppress local stiffness imbalances caused by the concentration or sparseness of connection points; c) a force transmission path balancing rule, used to constrain the contribution weight distribution of different connection points in the overall force transmission network based on the degree of influence of connection points on the load transmission path between the oil pan and the cylinder block, so that the load is distributed along multiple paths; d) a condition-sensitive adjustment rule, used to dynamically adjust the layout priority of connection points within different stability-dominant regions based on the vibration and thermal load evolution characteristics.

[0094] Furthermore, the generation of connection point spatial layout schemes includes: constructing a layout difference evaluation index to characterize the degree of structural difference between layout schemes based on the spatial distribution characteristics of connection points and the force transmission path organization characteristics corresponding to each connection point spatial layout scheme; the layout difference evaluation index includes the difference in the distribution of connection point locations and the difference in the coverage of force transmission paths; when the layout difference evaluation index between any newly generated connection point spatial layout scheme and an existing connection point spatial layout scheme is lower than a preset difference threshold, at least one rule parameter in the connection point layout generation rule is adaptively adjusted.

[0095] Furthermore, the identification of the set of stability-dominant regions whose overall stability contribution exceeds a preset threshold under multiple operating conditions includes: dividing the connection area between the oil pan and the cylinder block into multiple stability analysis sub-regions based on the connection action demand model; for each stability analysis sub-region, extracting regional-level contribution features that affect the overall connection stability under multiple operating conditions, the regional-level contribution features including regional stiffness contribution features, load transfer participation contribution features, and vibration response sensitivity features; for the same stability analysis sub-region, performing consistency analysis on the regional-level contribution features obtained under different operating conditions, the consistency analysis is used to identify regions that continuously and significantly affect the overall stability under multiple operating conditions, and to reduce the interference of regions that are momentarily prominent under individual operating conditions on the identification results; using the consistency analysis results to determine the stability contribution evaluation value corresponding to the workpiece in each stability analysis sub-region, and constructing the stability analysis sub-regions with values ​​exceeding the preset threshold as a set of stability-dominant regions.

[0096] Furthermore, the construction of corresponding connection coupling state models for the oil pan, cylinder block, and connection points based on the connection point spatial layout scheme includes: mapping the geometric positional relationships, assembly constraints, and connection topology relationships of the oil pan, cylinder block, and each connection point according to the connection point spatial layout scheme to form a structural relationship sub-model describing the spatial association and constraint conditions between the oil pan, cylinder block, and connection points; introducing corresponding connection stiffness characteristics, connection preload states, and load transfer characteristics into the structural relationship sub-model for each connection point to form a connection action sub-model characterizing the mechanical coupling behavior of the connection point between the oil pan and cylinder block; and coupling and fusing the structural relationship sub-model and the connection action sub-model to establish a connection coupling state model.

[0097] Furthermore, the construction of the connection stability evaluation tensor includes: extracting features from displacement response data, stress distribution data, and interface relative slip trend data obtained under multi-condition operating excitation; mapping the extracted response features to a unified numerical space according to a preset scaling rule; dividing the connection area into multiple spatial association units based on the topological structure of the connection area between the oil pan and the cylinder block; and aggregating the corresponding unique response features, stress distribution features, and interface relative slip trend features in each spatial association unit to form a unit-level multi-feature response vector; using the spatial association unit as the basic index dimension, mapping the unit-level multi-feature response vector to different feature dimensions of the tensor according to the response type to construct a connection stability evaluation tensor containing spatial dimension, response type dimension, and operating condition dimension, wherein the combination of different dimensions is used to characterize the joint distribution state of connection stability under different spatial locations, different physical responses, and different operating conditions.

[0098] Furthermore, the connection optimization method for improving the stability of the oil pan and cylinder block also includes: using the connection coupling state model to perform failure sensitivity analysis on each connection point and generate sensitivity indices for the corresponding connection points; and optimizing the target layout scheme based on the sensitivity indices.

[0099] Furthermore, the connection optimization method for improving the stability of the oil pan and cylinder block also includes: performing sampling verification according to the target layout scheme, performing sampling verification monitoring, generating monitoring feedback, and performing scheme self-optimization management of the target layout scheme based on the monitoring feedback.

[0100] Furthermore, the connection optimization method for improving the stability of the oil pan and cylinder block also includes: packaging and storing the connection point spatial layout scheme, calling the packaged and stored results according to the monitoring feedback, and performing scheme self-optimization management.

[0101] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The connection optimization device and specific examples for improving the stability of the oil pan and cylinder block in the aforementioned embodiment one are also applicable to the connection optimization method for improving the stability of the oil pan and cylinder block in this embodiment. Through the foregoing detailed description of the connection optimization device for improving the stability of the oil pan and cylinder block, those skilled in the art can clearly understand the connection optimization method for improving the stability of the oil pan and cylinder block in this embodiment. Therefore, for the sake of brevity, it will not be described in detail here.

[0102] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0103] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of this application and its equivalents, this application also intends to include such modifications and variations.

Claims

1. A connection optimization device for improving the stability of the oil pan and cylinder block, characterized in that, include: The module is used to construct a connection action requirement model based on the topology, material properties and assembly boundary conditions of the oil pan and cylinder block to describe the force transmission requirements and constraint relationships between the oil pan and cylinder block. The connection action requirement model is used to characterize the distribution of support requirement intensity for connection stability in different regions. The identification module is used to identify the set of stability-dominant regions whose overall stability contribution is higher than a preset threshold under multiple operating conditions after reading the vibration and thermal load evolution characteristics of the engine under operating conditions using the connection action demand model. The generation module is used to generate a spatial layout scheme of connection points within the stable dominant region using connection point layout generation rules. The coupling state construction module is used to construct the corresponding oil pan-cylinder block-connection point connection coupling state model based on the connection point spatial layout scheme. The evaluation module is used to apply multi-condition operating excitation to the connection coupling state model and construct a connection stability evaluation tensor based on displacement response, stress distribution, and interface relative slip trend. The configuration module is used to configure the target layout scheme based on the connection stability evaluation tensor.

2. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The generation module includes: The rule constraint unit is used to construct connection point layout generation rules based on the stability-dominant region to constrain the spatial distribution of connection points, wherein the connection point layout generation rules include at least one of the following: a: Force transmission coverage rule, used to constrain the minimum coverage density of connection points in the corresponding support requirement area based on the support requirement intensity distribution of different areas in the connection action requirement model; b: Layout dispersion constraint rules are used to set upper and lower limit thresholds for the spatial distance between adjacent connection points in order to suppress local stiffness imbalance caused by the concentration or sparseness of connection points. c: Force transmission path balancing rule, used to constrain the contribution weight distribution of different connection points in the overall force transmission network based on the degree of influence of the connection point on the load transmission path between the oil pan and the cylinder block, so that the load is distributed along multiple paths. d: Condition-sensitive adjustment rules, used to dynamically adjust the layout priority of connection points in different stability-dominant regions based on the vibration and thermal load evolution characteristics.

3. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 2, characterized in that, The generation module further includes: The index construction unit is used to construct a layout difference evaluation index to characterize the degree of structural difference between layout schemes based on the spatial distribution characteristics of the connection points and the force transmission path organization characteristics corresponding to each connection point spatial layout scheme. The layout difference evaluation index includes the difference in the distribution of connection point positions and the difference in the coverage of force transmission paths. The difference comparison unit is used to trigger an adaptive adjustment of at least one rule parameter in the connection point layout generation rule when the layout difference evaluation index between any newly generated connection point spatial layout scheme and the existing connection point spatial layout scheme is lower than the preset difference threshold.

4. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The evaluation module includes: The feature extraction unit is used to extract features from displacement response data, stress distribution data and interface relative slip trend data obtained under multi-condition operation excitation, and to map the extracted response features to a unified numerical space according to the preset scale transformation rules. Feature association unit is used to divide the connection area into multiple spatial association units based on the topology of the connection area between the oil pan and the cylinder block, and to aggregate the corresponding displacement response features, stress distribution features and interface relative slip trend features in each spatial association unit to form a unit-level multi-feature response vector. The evaluation tensor construction unit is used to map the multi-feature response vector at the unit level to different feature dimensions of the tensor according to the response type, using the spatial association unit as the basic index dimension, to construct a connection stability evaluation tensor containing spatial dimension, response type dimension, and operating condition dimension. The combination of different dimensions is used to characterize the joint distribution state of connection stability under different spatial locations, different physical responses, and different operating conditions.

5. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The identification module includes: The stability analysis region division unit is used to divide the connection region between the oil pan and the cylinder block into multiple stability analysis sub-regions based on the connection action requirement model. The regional contribution feature extraction unit is used to extract regional contribution features that affect the overall connection stability for each stability analysis sub-region under multi-condition operation. The regional contribution features include regional stiffness contribution features, load transfer participation contribution features, and vibration response sensitivity features. The contribution consistency analysis unit is used to perform consistency analysis on the regional contribution characteristics obtained under different operating conditions for the same stability analysis sub-region. The consistency analysis is used to identify regions that have a significant impact on the overall stability under multiple operating conditions and reduce the interference of regions that are momentarily prominent under individual operating conditions on the identification results. The evaluation value screening unit is used to determine the stability contribution evaluation value of each stability analysis sub-region workpiece based on the consistency analysis results, and constructs the stability analysis sub-regions with values ​​higher than the preset threshold into a set of stability-dominant regions.

6. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The coupling state construction module includes: The relation mapping unit is used to uniformly map the geometric positional relationship, assembly constraint relationship and connection topology relationship of the oil pan, cylinder block and each connection point according to the connection point spatial layout scheme, so as to form a structural relation sub-model describing the spatial association and constraint conditions between the oil pan, cylinder block and connection point. The characteristic introduction unit is used to introduce the corresponding connection stiffness characteristics, connection preload state and load transfer characteristics of each connection point into the structural relationship sub-model, forming a connection action sub-model to characterize the mechanical coupling behavior of the connection point between the oil pan and the cylinder block. The connection coupling state model establishment unit is used to couple and fuse the structural relationship sub-model and the connection action sub-model to establish a connection coupling state model.

7. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The configuration module includes: The failure sensitivity analysis unit is used to perform failure sensitivity analysis on each connection point using the connection coupling state model, and generate sensitivity indices for the corresponding connection points. The target layout scheme optimization management unit is used to optimize and manage the target layout scheme based on the sensitivity indicators.

8. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 1, characterized in that, The connection optimization device for improving the stability of the oil pan and cylinder block also includes: The sampling monitoring module is used to perform sampling verification based on the target layout scheme, execute sampling verification monitoring, generate monitoring feedback, and perform scheme self-optimization management of the target layout scheme based on the monitoring feedback.

9. The connection optimization device for improving the stability of the oil pan and cylinder block as described in claim 8, characterized in that, The connection optimization device for improving the stability of the oil pan and cylinder block also includes: The storage module is used to package and store the connection point spatial layout scheme, and to call the packaged storage results according to the monitoring feedback to perform scheme self-optimization management.

10. A method for optimizing the connection between the oil pan and the cylinder block, characterized in that, Performed by the connection optimization device for improving the stability of the oil pan and cylinder block according to any one of claims 1 to 9, the connection optimization method for improving the stability of the oil pan and cylinder block includes: Based on the topology, material properties, and assembly boundary conditions of the oil pan and cylinder block, a connection action demand model is constructed to describe the force transmission demand and constraint relationship between the oil pan and cylinder block. The connection action demand model is used to characterize the distribution of support demand intensity for connection stability in different regions. Using the aforementioned connection requirement model, after reading the vibration and thermal load evolution characteristics of the engine under operating conditions, the set of stability-dominant regions whose overall stability contribution is higher than a preset threshold under multiple operating conditions is identified. A spatial layout scheme for connection points is generated within the stable dominant region using connection point layout generation rules. Based on the spatial layout scheme of the connection points, construct the corresponding connection and coupling state models of oil pan-cylinder block-connection points respectively; Apply multi-condition operating excitation to the connection coupling state model, and construct a connection stability evaluation tensor based on displacement response, stress distribution, and interface relative slip trend; The target layout scheme is configured based on the connection stability evaluation tensor.

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