Abstract
A method of vibration analysis in the frequency range of high mode density is proposed. The aim of the method is to reduce the work to analyze modes by grouping many modes into several sets of modes. The grouping is assessed by similarity of the effects of structural modifications, which are made on the noticed portions of the structure. A representative mode is selected among the set of modes and analyzed instead of all modes in the sets. This saves much time for examining many mode shapes and so on. An application to automotive body presents the procedure for the interior noise improvement by modifications of the body structure. This application shows that this method is available for actual problems.
