WAVE-VECTOR-TIME DOMAIN AND KIRCHHOFF INTEGRAL-EQUATION METHODS TO DETERMINE THE TRANSIENT ACOUSTIC RADIATION LOADING ON CIRCULAR-CYLINDERS

Two new methods are presented to determine the transient acoustic radiation loading on circular cylinders. The acoustic modal forces are expressed as a sum of the convolution of the modal radiation impulse responses and the modal velocites. In the wave-vector-time domain method, the modal radiation impulse responses are obtained by using the radiation impulse responses of an infinite cylinder and the modes in wave-vector space. The approach can thus be easily used for parametric studies on the effects of boundary conditions and normalized lengths on the modal radiation impulse responses. In the Kirchhoff integral equation method, space and time are discretized. The pressure and acceleration in each element are then expressed in the form of a Taylor-series expansion about points at which the pressure is obtained by marching forward in time. The radiation impulse responses of both infinite and simply supported finite cylinders are obtained by the two methods and compared.