Bending Vibration Improvement of Automotive Outer Shell by Modifying Inner Structure.

Abstract

Bending vibrations of outer shells often cause serious problems. The shells cannot be always reshaped because the product style depends on them, and it is necessary to deal with coupled vibrations with inner structures to eliminate the problems. This paper demonstrates a FEM analysis of adjusting the coupled vibrations. In case of an automotive roof panel, FEM model determined by drawings, welding stiffness rate, and stamping thickness rate are contrived to simulate the roof vibration experiments. The analyses indicate that modifying rear inner structures contributes natural frequency increase more than 10%, and reinforcement and closed section of the rear inner panel and the outer panel is the most effective.