Acoustic radiation loading on cylindrical vibrators in an inviscid fluid with axial flow

Abstract

A wave-vector-time domain (k̄-t) method is presented to evaluate the acoustic radiation loading on cylindrical shells vibrating in an inviscid fluid with axial flow. The method is based on the use of the in vacuo modes of vibration of the shell that has infinite rigid extensions. The solution to the differential form of the acoustic wave equation for the pressure is first obtained in wave-vector-time space. The time-dependent modal forces are then expressed as a sum of the modal radiation impulse responses of the finite cylinder convolved with the time-dependent modal velocities. The modal radiation impulse responses are obtained by using the impulse responses of an infinite cylinder and the modes in wave-vector space. The approach can thus be easily used to obtain the radiation impulse responses for various boundary conditions, length to radius ratios, and arbitrary space- and time-dependent surface velocities. Numerical results are presented for a wide range of Mach numbers and length to radius ratios of simply supported cylindrical shells.