摩托车排气系统耐久性分析及结构优化

Durability Analysis and Structural Optimization of Motorcycle Exhaust System

摩托车排气系统的耐久性是评价其质量的重要指标,采用CAE技术分析摩托车排气系统疲劳耐久性并对其结构进行优化设计具有重要的理论研究意义和工程应用价值.建立摩托车排气系统仿真模型,并通过试验数据验证置信度;通过振动实验获得仿真输入的边界条件,计算排气系统机械应力与热应力分布云图;将应力分布作为边界条件,设置材料S-N曲线,计算排气系统疲劳寿命云图.仿真结果表明,支架两支耳连接处疲劳耐久寿命最小.根据仿真结果出现危险的位置提出三种优化方案,对比分析优化结果,针对最优方案制作实物并测试验证,试验结果表明:优化方案能达到耐久性设计要求.

The durability of motorcycle exhaust system is an important index to evaluate its quality.CAE technology is of great theoretical significance and engineering application value to analyze the fatigue durability of motorcycle exhaust system and to optimize its structure.The simulation model of motorcycle exhaust system was established,and the confidence was verified by test data.The boundary conditions of simulation input were obtained through vibration experiment,and the distribution nephogram of mechanical stress and thermal stress of exhaust system was calculated.The stress distribution was taken as the boundary condition,and the S-N curve of the material was set to calculate the fatigue life nephogram of the exhaust system.The simulation results show that the fatigue endurance life of the joint between the two ears of the bracket is the smallest.According to the simulation results,three optimization schemes were put forward for dangerous locations,and the optimization results were compared and analyzed.According to the optimal scheme,the real object was made and tested,and the test results show that the optimal scheme can meet the durability design requirements.