Finite Element Analysis And Optimization Of Connecting Rod Of An Engine

Internal combustion engine has been widely used in many fields.With the rapid development of society,people’s requirements for it are developing in the direction of higher safety,stronger stability and greater power,which also leads to its more stringent working environment.Connecting rod is a very important component in internal combustion engine.Its safety and stability are directly related to the reliability of the whole engine.In the working process of the engine,the connecting rod must bear the complex alternating load for a long time,so it is easy to appear deformation,crack and even fracture,which will directly affect the operation of the engine,and may endanger personal safety in serious cases.Therefore,in the process of the continuous development of internal combustion engine,the research on the performance of connecting rod is an indispensable link.In this paper,the connecting rod of a certain type of engine is taken as the research object.Firstly,the motion state and the stress condition of the connecting rod are analyzed and studied,and the theoretical values of the load of the connecting rod under the maximum tension state and maximum compression state under the calibration condition and overload condition are calculated.Then,a three-dimensional model of the connecting rod group is established and imported into the Workbench.Based on the theoretical data above,the static strength analysis of the connecting rod is carried out to calculate the stress and displacement results of the connecting rod under various working conditions and different states.Through the analysis of the results,it is concluded that the strength of the connecting rod meets the requirements.The modal analysis of the connecting rod is carried out,and the first 14 order free modes of the connecting rod are calculated.Through the analysis of the modal calculation results,it is concluded that the connecting rod of the engine does not resonance in normal operation.Then based on the previous strength analysis results,using professional fatigue analysis module to carry out fatigue simulation calculation of the connecting rod,the fatigue strength of the connecting rod meets the requirements.Finally,optimization design based on response surface method of connecting rod,and before the optimal design of connecting rod to the sensitivity analysis of parameters,select the output parameters affect the big characteristic parameters as the input parameters of optimized design,and then the response surface model was constructed,and check the accuracy of the model,based on this model,the first objective function with the connecting rod body quality lightest for optimization solution,The mass of the optimized connecting rod decreases by 6.88%,and the strength of the optimized model is verified to meet the requirements.