Sound power determination from surface intensity measurements on a vibrating cylinder

The feasibility of using surface intensity measurements for the determination of sound power as a tool for noise source identification was studied with an experiment on a circular cylinder. This cylinder was an idealized model of a muffler shell of a heavy diesel truck. Two experiments were performed with the cylinder excited by an electromagnetic shaker. In the first one, the shaker was driven with a one‐third octave band of white noise centered at 6300 Hz and in the second experiment it was driven with broadband white noise between 1000 and 5000 Hz. The sound power measurements were made in a reverberant room and the reverberant room method was used to provide a comparison with the sound power levels obtained from the surface intensity measurement. The acoustic surface intensity was computed from the cross‐spectral density between the acoustic pressure and the normal surface velocity of the cylinder. An equation was developed to allow for inclusion of a correction for phase shifts that were caused by th...