The acoustic wave from a shock-vortex interaction: comparison between theory and computation

Experimental, theoretical, and computational research has shown that the in teraction of a shock with a vortex produces a quadrupolar acoustic wave. Al though the theoretical basis for this has been accepted for some time, ther e has not been a detailed comparison of the predictions for the pressure va riation around and through the acoustic wave to the pressure fields obtaine d from numerical simulations. In this paper, Ribner's theory is used to pre dict the acoustic pressure field evolving from a shock interacting with eit her a Rankine (or infinite) vortex or with a composite (or finite) vortex. A comparison of these theoretical results indicates the importance of vorte x geometry on the acoustic wave. Then the theoretical results are compared to the results of detailed computations. The computational results were obt ained by solving the two-dimensional conservation equations for mass, momen tum, and energy for a compressible, inviscid fluid using the Flux-Corrected Transport algorithm. These results show that there is good qualitative agr eement between the theory and the computation. (C) 2000 The Japan Society o f Fluid Mechanics and Elsevier Science B.V. All rights reserved.