Study on Comprehensive Design-Decision-Making in Tribological Design for Internal Combustion Engine

Tribological design for engine is characterized by multipurpose, multiconstraint and multiparameter, with most of its design inference procedures to be nonserial and of comprehensive decision making procedures. A new knowledgeembedded evolutionary design algorithm is proposed, which can combine the algorithm's parallel design ability with experts' intelligent ability. Therefore, the comprehensive decision procedure is simplified to choosing an acceptable solution in a feasible solution population. An expert modifying operator and an empirical marked operator are designed and excellent design solutions for piston assembly system are obtained. However,"parameterdominating phenomenon" and "subsysteminterfering phenomenon"emerge in evolutionary design for the whole set of an engine. Thus a hierarchy gene model is built up to solve this problem. The corresponding hierarchy cooperating evolutionary design method and its parameterbased cooperating mechanism are also proposed. The application of the hierarchy gene model in the tribological design of a whole set engine is introduced.