摘要
为实现发动机排气系统在各种工作状态下的复杂热振动疲劳性能评估,文章通过对输入数据的测量和模型的简化、对标,建立等效仿真模型。采用时域的结果对排气系统热端评估热振动疲劳,研究了温度、制造公差对疲劳结果的影响范围,量化了安全系数指标范围。在焊缝疲劳方面,建立实体焊缝模型,规范焊缝建模参数,以主S-N曲线法为核心算法进行新的应用评估,运用临界插值法计算等效结构应力,克服了焊缝加载模式依赖性强、网格类型及尺寸大小要求严格等问题。此评估方法能支持排气系统设计方案对比选型,为焊接方案更改提供快速评估,在实际应用中具有指导意义。
In order to evaluate the complex thermal vibration fatigue performance of engine exhaust system under various working conditions,the equivalent simulation model is established by measuring the input data,simplifying and benchmarking the model.The time domain results are used to evaluate the thermal vibration fatigue of the hot end of the exhaust system.The influence range of temperature and manufacturing tolerance on fatigue results is studied,and the targets of safety factor are qualified.The solid weld model is established to standardize the weld modeling parameters.The principal S-N curve method is used as the core algorithm for new application evaluation,and the critical interpolation method is used to calculate the equivalent structural stress.It overcomes the problems of strong dependence of weld loading mode and strict requirements of mesh type and size by old method.This evaluation method can support the exhaust system design scheme comparison and selection,and provide rapid evaluation for welding scheme change,which has guiding significance in practical application.
作者
王慧玲
刘耀东
WANG Huiling;LIU Yaodong
出处
《上海汽车》
2022年第1期43-50,共8页
Shanghai Auto
