It is effective to analyze the camshaft strength through FEA method during the design phase. The dynamic loads on camshaft could be got by using one-dimensional dynamic simulation on valve train. Then the three-dimensional transient dynamic FEA could be carried out, when the one-dimensional simulation result was as input loads. The strength evaluation of camshaft could be crarried out after the stress course was calculated. With practical experiments, this method is proved effective to check design scheme and provide reference for choosing camshaft material.

By establishing a one-dimensional dynamics simulation model of valve train,the dynamic loads on camshaft were calculated.Based on the one-dimensional simulation results,a three-dimensional transient dynamics analysis was carried out by using FEA.And the stress course during camshaft running was calculated and the camshaft strength was evaluated.The fatigue strength was computed by using FEMFAT to predict fatigue characteristic of the camshaft.This method can be used to confirm the design scheme of camshaft and to provide a reference for selecting camshaft material.

连杆在发动机工作过程中承受复杂的载荷.通过运动学和动力学分析获得连杆的载荷和边界条件,建立有限元模型.将复杂的连杆载荷分解为预紧工况、装配工况、爆压工况和惯性工况实施有限元计算,对其各种指标进行评价.将预紧工况、装配工况和惯性工况计算结果叠加,评价杆身与大头盖接触面的压力分布.最后采用基于有限元计算结果的疲劳分析方法获得连杆的疲劳安全因子分布,评价其疲劳特性.根据分析结果对连杆进行改进,获得了良好的效果.实践证明,该方法能有效地指导连杆的设计工作.

A model of body frame of touring coach is set up according to the finite element method(FEM),The strength,stiffness,modal analysis and simulation calculation of body frame structure have been done under working conditions of plane bending,utmost torsion,urgent turning and emergency braking based on this model,and the distribution condition of stress,strain,torsion moment,bending moment of structure are obtained.The static stress test verifies the correctness of the model.

Vehicle exhaust system rubber hangers are the main ways to transfer the vibration energy to the vehicle body,and reasonable hanger locations can effectively decrease the transfer of the vibrations and energy.Based on load transfer,the average driving DOF displacement(ADDOFD) is applied to modal analysis,and the hanger locations are determined.The static and dynamic analysis and the frequency response analysis are made to verify the layout reasonableness.

Topology optimization of an engine accessory bracket is conducted by using the method offered by the Optistruct software.An initial structure is created based on the interspace left by the layout of accessories,and multiple static and modal analyses are carried out in order to obtain basic stiffness and modal information.Then a model which minimizes the structural weight with the displacement and frequency constraints for multiple loading cases is defined.The simulation yields an optimal topology.According to the optimal topology and some other factors,a new design is created and FEA is made to validate the design.The results show that the method can offer an accessory bracket light in weight and maximum in stiffness.

A wire-frame model for the body skeleton of a bus is built by utilizing Unigraphics software and then translated into the finite element model by ANSYS software through the programs designed.The static strength analysis on the body skeleton is carried out based on finite element method.The loading characteristics of the skeleton of unibody are investigated.A scheme of local modification in some part of structure is put forward with an aim to enhance the strength of complete structure.The strength tests on both modified and original bus bodies are conducted and the results verify the rationality and reliability of the improved structure.

The overall objective of this study is to discuss the stiffness characteristic of tires.The relationship between the stiffness characteristics and the deflection of tires was built.In this study,a detailed finite element model of a radial tire was constructed for the prediction of stiffness characteristics.The strategies of solving computational cost were proposed.A procedure was introduced for the simple and accurate determination of tire cross-sectional geometric characteristics.The nonlinear mechanical properties of the elastomer were modeled by the Mooner-Rivilin model and the corresponding material constants of elastomers were obtained by experiment.The model of the relationship between the slip angle and tire deformation was constructed.The calculated results are compared with the experimental results and it shows that the model reliability is fairly good.

将轮胎的有限元分析计算结果引入到轮胎静态侧偏特性研究中,利用轮胎的有限元分析结果得到轮胎侧偏刚度.为控制网格划分的密度与质量,采用数字化轮廓技术,在UG软件中绘制轮胎断面曲线,将离散化后的曲线信息导入有限元分析软件ANSYS中.建模时充分考虑了橡胶材料的超弹性和各向异性,材料模型采用Mooney-Rivlin橡胶材料.计算结果和试验结果验证了理论计算的可靠性.

Dynamic properties of tires are one of important indexes which affect unitary performance of vehicles. In this paper, a radial tire non-linear finite element analysis(FEA) model is built in the ANSYS environment with the non-linear characteristics of radial tire's materials fully considered,and modal analysis is performed based on this model,then the natural frequency and vibration mode are obtained.The results have a guiding value in practice and are beneficial to the radial tire's other dynamic analyses in succession and the study on contribution of tire properties to the whole vehicle performance.

The effect of ground’s constraint on the modal characteristics of tires is studied. A detailed finite element model of the radial tire is constructed for the prediction of modal characteristics. The contact constraint of a radial tire structure with rigid road and rim is treaded with the variable constraint method. The strategies of solving computational cost are presented. A procedure is introduced for the simple and accurate determination of tire cross-sectional geometric characteristics. The nonlinear mechanical properties of the elastomer are described by the Mooney-Rivlin model and the corresponding material constants of elastomers are obtained by experiment. Numerical results show that the effects of the contact constraints are obvious.

Tire'e performance has a great effect on that of automobile. So, its situation is very impor tant. With the development of the computer,we can analyze the characters of the tire by FEA. In this pa per , we make use of the software ANSYS to find the 3D finite element model of tire. Solid - element and layer-element were chosen. According to the non-linear theory, different conditions of tire were simulated. As a result,the stresses,strains and deformations of tire were achieved.