Planar blast/vortex interaction and sound generation

By the use of a fifth-order weighted essentially nonoscillatory scheme to solve the two-dimensional, unsteady compressible Euler equations, a planar blast/vortex interaction is investigated in detail. The effects of the initial blast Mach number Ms and vortex Mach number Mv are discussed and compared with the corresponding cases of shock/vortex interaction. The sound generated by the planar blast/vortex interaction is also studied. It is found that the radial pressure peaks of the first sound for the cases of shock/vortex interaction are larger than those for the cases of blast/vortex interaction. However, the radial pressure peaks of the second sound in the blast/vortex interaction can be larger than those in the corresponding case of shock/vortex interaction. This is due to the effect of the secondary shock interacting with the vortex, enhanced by the expansion waves following the blast-wave front. In addition, an interesting phenomenon of the fourth sound, which is an exception from the first three sounds generated by the blast/vortex interaction, is found that does not occur in the case of a shock/vortex interaction.