Performance Analysis And Optimization Of Automobile Powertrain Mounting System

Riding comfort has been a focus of people as the widespread use of automobile. The noise and vibration mainly come from the automotive engine, so during modern automobile design, the effective solutions to isolate the vibration of engine are very important. On the one hand, to restrict the motions of powertrain, the mounting system is required to be designed with a large stiffness. On the other hand, to improve the mounting system’s anti-vibration performance, it should be as’soft’as it can be. The NVH performance of vehicles can get a good improvement by a reasonable design of powertrain mounting system.This subject contains following work by taking a certain powertrain mounting system of passenger car as research objects.1. By consulting a number of literature, the study of powertrain mounting system at home and abroad were analyzed. Related parameters, such as powertrain physical parameters and mount stiffness, were measured to make up foundation for future work.2. Theoretical mechanics model and multibody dynamics model of powertrain mounting system are established in MATLAB and ADAMS separately, analysized the first six order modal and energy decoupling rate, and evaluated the system by relevant theoretical knowledge.3. Multibody dynamics software were used to create a powertrain mounting system model based on the 28 working conditions which generally used in North America, chose some typical of these conditions to calculate the displacement of powertrain and mounting system, and also the force of them. The stiffness of the system used in the process was nonlinear.4. The modal and strength analysis of the stent which combine the vehicle body and the mounting system was carried out to ensure the rationality of the design of the mount bracket.5. With setting the stiffness as design variable, limiting the variable range and restraining the powertrain inherent frequency, optimized the decouple rate of mounting system.After the optimization, the anti-vibration performance was improved. This research had certain reference significance to the optimization of the powertrain mounting system design.