Analytical Investigation On Dynamic Characteristics And Vibration Control Of Powertrain

Design of internal combustion engine is making continuous development toward high-speed, light and large power. Research on reliability design and vibration and noise reduction of internal combustion engine become more and more important due to requirements for high performance, low cost and fast-to-market engine designs.Focusing on vibration isolation of powertrain, the dynamic characteristic of a diesel engine block and its powertrain are studied by using modal analysis theory and finite element technique to provide for improvement of vibration reduction of powertrain.In this paper, firstly the vibration level of the diesel engine block is evaluated after it's vibration is tested, vibration of the engine and it's powertrain on a bus is also tested and evaluated to find out the reason that causes serious vibration when the engine is fixed to the bus; secondly, experimental geometric model of the engine block and transmission are established, and their dynamic characteristics are studied by experimental modal analysis method; thirdly, 3D solid models of engine block, crankcase, transmission and powetrain are established under Pro/Engineer environment, at the same time, the finite element model of the engine block and the powertrain are established, the model frequencies and models are obtained, compared with the model experiment's results, we find that the finite element model established has enough accuracy; the model frequencies and models of the powertrain are also calculated to provide for adjustment of it's supporting position; at the end, the improvement that is changing supporting position from transmission to flywheel housing is proposed and validated, the result shows that changing the supporting position of powertrain can isolate the vibration.