A Research On Dynamic Decoupling Method For A Powertrain Mounting System

Good ride and low noise are important symbols of modern cars. Vibration of powertrain is a main vehicle vibration source of excitation in the whole vehicle vibration, which has significant influence of a car's comfort and NVH characteristics. The rational design of powertrain mounting system can reduce vibration to transfer and improve the NVH performance of vehicles, which becomes an important research topic. Decoupling mounting system design and reasonable allocation of the natural frequencies are equally important goals in obtaining a reasonable layout of the mounting systemFirstly, this paper shows that the excitation of engine is the main incentive of vehicle vibration. A simplified model of powertrain mounting system is established, then the method of energy decoupling and torque roll axis decoupling are studied based on it. This paper mainly study on the theory of torque roll axis decoupling, especially with the damping mount system, and the decoupling layout of the mounting system. Torque roll axis decoupling has great significance in the decoupling of with damping mount system.Secondly, the optimization theory of powertrain mounting system is cited. Decoupling optimization and decoupling-reducing peak of displacement response optimization are carried out both in the crankshaft coordinate system and torque roll axis coordinate system. The calculate results show that decoupling optimization get better decoupling rate in the torque roll axis coordinate system, and decoupling-reducing peak of displacement optimization get lower response peak in torque roll axis coordinate system.In the end, based on the isolation theory, vehicle on the installation of the 3 status mount experiments at idle speed. The results of the experiment with the performance of vibration isolation mount system select a set of the best performance of vibration isolation mount. The best status of mount at the idle speed traveling four road speed on second ring road and the stone road, determine when the vehicle traveling on the road, the vibration isolation performance, and obtain the importance of vehicle vibration isolation.