Estimation of structure-borne noise in plates for far field conditions using the structural intensity method

Vibration power flow measurement is an important tool in identifying significant paths of vibration transmission from source through a structure. The measurement of vibration level itself may give limited information since stationary waves may be present giving rise to large amplitudes with no power transmitted. Structural intensity is a vector quantity where the power flow pattern may be identified by measuring the structural intensities on the structure. This paper examines the use of structural intensity in the theoretical estimation of vibration power flow in naturally orthotropic plates in the frequency domain under far field conditions. The theoretical power flow models could be used in technically orthotropic plates and corrugated plates for example by defining the elastic rigidity constants using the method of elastic equivalence [2].