Research on the modification technique on structural dynamic model of complex I.C.E. components

To improve accuracy of FEM models used in structural dynamic response or acoustic prediction analysis, a software named FEMM was developed based on the theories of dynamic sensitivity analysis and macro-treatment of dynamic modification. Taking a V6 diesel engine's lower crankcase as an example, the method and processes using FEMM model were described. Modification results show that the coincidence in modal frequencies between testing and analysis, the FRFs between the tested and the synthesized from analyzing model were improved. The software could be effectively applied to modeling of the complex engine components and improve the analyzing models' accuracy.