Theoretical calculation and experimental analysis of the rigid body modes of powertrain mounting system

-The performance of dynamic property of the mount is influenced by multiple factors and strongly depends on the working conditions. This means that the modal parameters of powertrain mounting system would make changes under different operating conditions. A novel approach to simulate the actual working condition is proposed in the testing of dynamic stiffness. Then the mechanical model of powertrain mounting system based on dynamic stiffness is established in this paper. In order to examine the rationality and accuracy of the computational model based on dynamic stiffness; experimental modal analysis is performed by multiple means and methods in this paper. Through the contrast analysis, advantages and disadvantages of these methods are illustrated and it is shown that using the method of Operational Modal Analysis could obtain more accurate and more reliable results. Based on the experimental and evaluation results, it is shown that there is smaller relative error and higher fitting degree between the calculation results based on dynamic stiffness and the results obtained from operational modal analysis. Moreover, the proposed method also enjoys satisfactory consistency with the actual working condition. Key-Words: Powertrain mounting system; Dynamic stiffness; Static stiffness; Operational Modal Analysis; Rigid body modes; Experimental modal analysis; Impact hammer testing