Focusing of the Rarefaction Wave in a Thin Cavitating Fluid Layer with a Free Boundary

Resumo

A new method of focusing the rarefaction wave in a one-dimensional axisymmetric formulation is proposed. The method is based on shock wave generation initiated by motion of a piston coaxial with the axis of symmetry with a prescribed pulse profile for the maximum velocities of 20 to 100 m/s and the exponent decay constant up to 10 μs. It is found that reflection of the shock wave from the free boundary generates a rarefaction wave propagating toward the axis of symmetry with increasing amplitude, and a cavitation zone is formed and developed behind the wave front.