诊断、建模、灵敏度分析和优化设计——发动机支承改进设计四步法

Diagnosis,Modeling,Sensibility Analysis and Optimal Design-Four-Steps Process in Improvement Design for Engine Mounting System

本文结合DD680大客车发动机支承系统改进设计实例,介绍解决这一问题的“诊断——建模——灵敏度分析——优化设计”四步程式及其有关方法。其中包括1、运用相干功率谱、互谱——相位法等手段诊断支承系统存在的问题。2、构造两步最小二乘法,用以辨识支承系统动力学模型。3、进行灵敏度分析,剔除设计变量中的不灵敏因素,化简数学模型。4、应用模糊集理论,通过“移频、解耦、降低支承处响应力”等多种途径对支承参数进行模糊多目标优化,最终获得了较为满意的综合效果。

With the example of improvement design for DD680 coach's engine mountingsystem this paper presents four-steps process. It begins by effective diagnosing pro-blems of design in engine mounting system, then 'two-steps method of the leastsquare' is used to identify the model of dynamic system.Thirdly, by help of sensi-bility analysis of design variable, unsensitive design variables in math model can bedeleted. Finally, a method about fuzzy multi-objects optimization is applicaled to co-ordinate the conflicts coming from sub-objects and to find a satisfactory solution.