Driveline Boom Noise Reduction through Simplified FEM Approach

In today's competitive automobile marketplace with reduced vehicle development time and fewer prototypes/tests, CAE is playing very crucial role in vehicle development. Automobile environment demands ever improving levels of vehicle refinement. Performance and refinement are the key factors which can influence the market acceptance of vehicle. Driveline is one of the key systems whose refinement plays critical role in improved customer satisfaction. Because of the virtue of the driveline functionality, driveline induced noise and vibration are the most common issues in the AWD vehicle development programs. Refinement of the drive line needs complicated nonlinear full vehicle CAE MBD models for the evaluation of driveline induced noise and vibration responses at different operating conditions [1]. In this paper a simplified approach is adapted for solving the Noise & Vibration issue which has been identified at the prototype testing level of an AWD vehicle development. Linear finite element method is used as a basic tool in identifying the root cause and propose the design solution. In presented work full flexible FE driveline model was built for modal analysis and the ODS was matched with test behavior. After establishing the correlation between the FE and Test, different system variables were optimized to reduce the system level response. Later these solutions were evaluated for seat vibrations and cabin noise levels. This technique can be used where the time, resources and system inner details are not available or those are limited to build the complete nonlinear CAE models. With this simplified approach it was possible to quickly resolve the driveline induced N&V problem.