Optimality for Sound Pressure Minimization in Vibro-Acoustic System and Structural Optimization (2nd Report Sound Pressure Minimization at Natural Frequency)

The sound pressure in the frequency domain is expressed by a scalar product of a structural frequency response function (FRF) and an acoustic FRF. Therefore, the optimality condition for sound pressure minimization is that, the amplitude of the sound pressure is zero when structural FRF and acoustic FRF are orthogonal. In this paper, sound pressure minimization at natural frequency is considered, based on the optimality condition. The acoustic FRF is not variable for structural modification in low frequency range. Therefore one can recognize at which frequency the structural vibration is easily transmitted to the sound pressure. And a novel efficient optimization approach based on the above knowledge is proposed.