Design Optimization of an Engine Mount for Enhancing Vibration Isolation Capability

Design optimization of an engine mount system for enhancing vibration isolation capability is performed in this study. Eleven position values and twelve stiffness values of four engine mounts are optimally determined in order to maximize kinetic energy fractions at six natural frequencies while satisfying fourteen design requirements on natural frequencies, differences between natural frequencies, distance between the torque roll axis and the line connecting the LH mount and the RH mount. The automobile engine is modeled as a point mass and supported by four engine mounts. Modal analysis is performed using MSC.NASTRAN, and the analysis procedure is integrated and automated by PIAnO, a commercial PIDO (Process Integration and Design Optimization) tool. Optimization is performed using PQRSM (Progressive Quadratic Response Surface Method), one of the optimization techniques equipped in PIAnO. Design optimization result reveals that the minimum kinetic energy fraction has been increased by 47.9 % while satisfying all the design requirements, which demonstrates the effectiveness of the design optimization approach used in this study