Multidisciplinary Design Optimization for Wobbleplate Engine Piston of Torpedo Based on iSIGHT

To solve the multidisciplinary design optimization(MDO) problem for wobbleplate engine piston mechanism of a torpedo, a MDO model is built based on multidisciplinary feasible(MDF) method with comprehensive consideration of structure, temperature, and intensity of the piston. A temperature field model and a stress model of the piston are built by UG and ANSYS, and multidisciplinary optimization analysis and design are conducted by means of numerical analy-sis and calculation. MDO platform and simulation process are constructed by integrating iSIGHT with UG and ANSYS. Through secondary development of the software, the parameters import, export, and automatic update, as well as the data exchange among different software, are realized on the MDO platform. The MDO results illustrate that the weight of the piston is reduced by 21.81%, the peak temperature and the temperature of the first ring groove decrease by 55℃ and 29℃, respectively, and the maximum stress decreases by 10 MPa. Simulation results show that the MDO method can im-prove the characteristics of temperature and thermal stress of the piston, and can deal with the coupling of heat and structure effectively, and can promote MDO efficiency.