Analysis And Optimization On The Static And Dynamic Loads Of Connecting Rod And The Transformation Of Equivalent Static Loads From Dynamic Loads

Connecting rod is the key part of engine,its structure and force are complex.The strength of the connecting rod is directly related to the service life of the engine.With the development of industrial technology,the requirements on the engine is higher,requirements on the quality is as small as possible under the condition of enough strength and stiffness of connecting rod,which makes the work environment of connecting rod become increasingly harsh.Therefore,it is more and more important to analyze the motion and force of the connecting rod,as well as calculate the structural strength of the connecting rod and optimize the connecting rod.A model of diesel engine is regard as the research object.Firstly,the connecting rod's bearing load at the actual work process is calculated through the actual stress curve.Secondly,based on the simplified model,the connecting rod is built with APDL language by using the finite element analysis software ANSYS,and then static analysis of the connecting rod is carried out by using the finite element analysis software ANSYS,and the stress diagram and displacement diagram are obtained.Then,defining the design variables,objective function and constraint conditions,optimizing the connecting rod staticly with multi Island genetic algorithm by using integrated optimization software ISIGHT.Then,the transient dynamics analysis of the connecting rod is got by using the ANSYS software and the dynamic optimization of the connecting rod is carried out by using orthogonal experiment method.Finally,the representative 12 nodes on the surface of the piston pin are selected as the nodes to carry out the transformation of equivalent static loads from dynamic loads.The maximum displacement time of the nodes is regard as the critical time points to make the transformation.Then,the stress and displacement of connecting rod under equivalent static loads and static loads are compared,the results show that the error of stress and displacement is within reasonable range,which verifies the reasonableness and reliability of the equivalent static loads.