In this study, mold design conditions were optimized by CAE parameter design to reduce variations in intake and exhaust port dimensions that influence the characteristics of a new type of rotary engine. The parameter design was performed by carrying out a direct product experiment without setting separate noise factors because, in view of the numerous types of error occurring at mold manufacturing sites and the complex interrelationships thereamong, optimization under various combinations of noise factors would be necessary, requiring lengthy CAE procedures. Efforts were made to simplify the CAE models, and a fully automated analytic system was constructed. To confirm their validity, the simplified models were compared with realistic models; the results indicated extremely high reproducibility. When factors with large effects were applied in actual core cylinders, dimensional variation of the intake ports was reduced by a factor of 1/2.5.
