解析目标分流法在汽车多学科设计优化中的应用

Application of Analytical Target Cascading Method in Multidisciplinary Design Optimization of Automobile

在阐述分解协调策略和研究ATC方法计算流程基础上,利用基于二次罚函数的ATC方法对某发动机燃烧室进行多学科设计优化(MDO)研究。考虑几何和热力学两个学科,很好地解决了学科间复杂耦合带来的计算困难,计算结果与不分解优化的结果非常接近,验证了该方法在汽车设计中的有效性。同时研究了步长对优化结果的影响,发现随着步长加大,误差变大,计算成本变低。

Decomposition and coordination strategy was presented and the computation flow of ATC method was studied, on this basis, ATC method based on quadratic penalty function was applied to multidisciplinary design optimization （MDO） of combustion chamber of an internal combustion engine. Two disciplines are considered in the design case, namely geometry and thermodynamics. ATC method can deal with the complex coupling among these disciplines and the results extremely approximate to the results of non-decomposition optimization method. Validity of this method is proved in auto design. The effect of step length on the result of optimization is also studied, a phenomenon is found that error becomes bigger and computation cost becomes lower along with the step size increases.