The Study Of Vibration Isolation And Optimization Of Mount System Of Powertrain For A Domestic Car

Ride comfort is an important performance indicators for motor vehicles,especially for car. The performance of powertrain mounting system have an important impact for a car ride. Good performance powertrain mounting system can not only reduce powertrain vibration transmission to the chassis, reducing vehicle noise, thereby improving comfort, but also better protect the powertrain.Vibration caused by the vehicle has two main vibration source.The first is the road random excitation; Second, the vibration is the engine work incentive. On the one hand, with the improvement of road conditions and car suspension system design complete, the road random excitation have eased the comfort of the car ;the other hand, the design of modern car stressed the lightweight,using a new type of high-intensity lightweight materials in order to reduce vehicle quality, but the quality of the engine will be difficult to reduce. Thus, the quality of motor vehicle is rising in the proportion of quality. However, the modern engine is more than the four-cylinder four-stroke engine with a poor balance ; cars use the thin-walled structure of the whole body, then the flexibility of the body increased, vibration trend rised engine vibration incentives of the vehicle relative increase. Above factors make a car engine vibration become the main vibration source, its speed and torque output of cyclical imbalances and the inertial force (moment) powertrain itself aroused both the rigid and elastic vibration, and aroused car Powertrain the torsional vibration, bending vibration, and the various vehicle vibration and vibration caused these air resonance inside the noise, resulting in very complex vibration, noise and structural fatigue problems.How to design high-performance vibration isolation mounting system to effectively isolate the transmission of engine vibration to the body , automotive design is an important aspect. The main performance parameters with impacting vibration isolation of the mounting system is the mount stiffness, installation location and installation perspective.The main objective of Mounting System Design is getting a reasonable stiffness, installation location and installation perspective, then the mounting system could have excellent performance vibration isolationIn this paper, based on domestic export car of a company , establish the powertrain mounting system model of the vehicle ,then get research of powertrain mounting system for the isolation and optimization , including the following aspects:1. Through finding and reading a lot of literature, from the research of mount components, design of the mount systems, systematically introduce and summary the situation at home and abroad as well as previous research results in detail. At the same time, systematically summarizes the powertrain mounting system designed criteria and designed requirements, as well as mounting system optimization design principles and theories.2. Analysis of the powertrain mounting system designed principles, and the matching of powertrain mounting system and vehicle design. Established rubber mount and hydraulic mounts equivalent mechanical model,then in this building, established the powertrain mounting system of 6-DOF model, and analyzed the excitation of the powertrain. Use the model, the inherent characteristics of static analysis, dynamic analysis and system transfer rate calculation methods of the mounting system are gotten.3. The basic parameters of Powertrain mounting system for modeling, such as the quality of powertrain, centroid location and moment of inertia, as well as the location of Mount parameters and stiffness, have done the actual measurement experiment work.4. Based on the theory of multi-body dynamics and vibration theory, through on the measured parameters, establish the powertrain mounting system ADAMS model. Under the ADAMS software model of the inherent characteristics of a specific analysis, the model may be pointed out that the optimization direction. Then from the two idling and high-speed conditions, the vibration response of the model were analyzed.5. This paper takes the energy decoupling of the powertrain mounting system as the optimizing goal and the stiffness parameters of the mount components were optimized design variables, then have been relatively satisfied with the results.