Abstract
In order to obtain the vibration response characteristics of the engine mount, its constrained modal analysis was completed based on the finite element method. The mesh of the contact part between the bolt head and the bracket part was considered as shared node, achieving the simulation of compressive contact between the bolt and bracket parts. The simulation results of natural frequencies and modal shape were verified through constrained modal experiments. The results indicated that the accuracy of the simulation results is high, and the maximum deviation between the natural frequency and the experimental value is less than 5 %. Compared to higher-order modes, the preload had a more significant impact on lower order modes. Based on the modal analysis results, reasonable excitation vibration directions were set, and the dynamic stiffness of the model was simulated and tested within the frequency range of 2400 Hz, providing important basis for optimizing vibration isolation performance.