A decoupling method of powertrain mounting systems and vibration characteristics analysis of complex flexible foundations

Abstract

A dynamic model of a powertrain mounting system was derived to explore multi-dimensional coupling vibration of the powertrain. Then six degree-of-freedom natural frequencies were calculated and decoupling conditions of the most important vibration modal were confirmed. A powertrain mounting system of heavy truck was designed and verified. FEM and the power flow theory were combined to explore flexible vibration of complex foundations in engineering. Modal information of complex foundations can be obtained from FEM and taken into vibration power functions. Then vibration power transmitted in the vibration isolation system with complex flexible foundations can be obtained. The results show that obvious and dense peaks of vibration power appear because of foundation flexibility, isolation effect has deteriorated at middle and high frequencies. Foundation flexibility is essential to vibration transmission in the whole system. The increase of foundation rigidity is beneficial to vibration isolation. The new method is practically significant to explore flexible vibration isolation systems with complex foundations in engineering.