Optimization of Damping Treatment for Structure Borne Noise Reduction

In automotive industry, all passenger vehicles are treated with damping materials to reduce structure borne noise. The effectiveness of damping treatments depends upon design parameters such as choice of damping materials, locations and size of the treatment. This paper proposes a CAE (Computer Aided Engineering) methodology based on finite element analysis to optimize damping treatments. The developed method uses modal strain-energy information of bare structural panels to identify flexible regions, which in turn facilitates optimization of damping treatments with respect to location and size. The efficacy of the method is demonstrated by optimizing damping treatment for a full-size pick-up truck. Moreover, simulated road noise performances of the truck with and without damping treatments are compared, which show the benefits of applying damping treatment. Finally, the optimized damping-treatment configuration is validated by comparing the locations and the size of the treatment with that of a laser vibro-meter test conducted on body-in-white (BIW) structure of the truck. The paper also presents a brief discussion of a few other applications in which the proposed method has been applied successfully at DamilerChrysler Corporation in optimizing damping treatments.