자동차 엔진마운트용 고무에 대한 변형 특성 해석과 형상 최적 설계

The hyperelastic and viscoelastic behaviour of rubber material is described. Uniaxial tensile tests and planar tests are carried out and the test data are verified by simple analysis with one element. Static characteristics of rubber engine mount is analyzed by using the 2D and 3D finite element model. The 2D plane strain model is well corresponded with the 3D model in the aspects of deformed shape, stress distribution and reaction force. With these results and basic shape factor(parameter), optimum shape design process of engine mounting rubber is introduced. The secondary stiffness and the gap size of engine mount are determined by nonlinear spring analysis. The optimum shape design process of engine mounting rubber using a parametric approach is suggested. An optimization code is developed to determine the shape to satisfy the characteristics of mount, which is executed with the commercial nonlinear finite element code. Two engine mounts are designed by the procedure mentioned above. The stiffness values of the final optimized models along the principal direction are compared with the design specifications.