Author(s)

Rokhsan Ara Hemel¹, Hiroyuki Hirahara², Kento Takahashi¹

¹Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
²Faculty of Engineering, Saitama University, Saitama, Japan.

The present paper has investigated the momentum transport phenomena of underwater shock wave generation in terms of photo-acoustic wave with a very thin metal. The shock wave was induced by a pulsed-laser irradiation. In order to clarify the momentum transport mechanics in this phenomenon, we have been considered the momentum and energy transport from laser to metal, and metal to water. A numerical solution of thermo-elastic wave in metal has been obtained to estimate a fundamental gain of the longitudinal wave. Then, the underwater shock wave phenomena have been analyzed by adapting compressible fluid dynamics with suitable boundary condition between the solid and liquid. We had performed an experiment as well and observed the shock wave with optical system. The aim of the research is to estimate the underwater shock wave strength theoretically. The metal region was calculated by Laplace transformation of heat conduction and wave equations. The water region was simulated by MacCormack’s method. Some of boundary conditions have been examined and the acceleration condition has been adopted at the interface. The simulated results show a good agreement with experimental result, consequently the momentum transfer mechanism from longitudinal wave to underwater shock wave has been cleared in the present report.

Momentum transfer, Underwater shock wave, Longitudinal wave

Ara Hemel, R. , Hirahara, H. and Takahashi, K. (2016) Momentum Transfer on Underwater Shock Generation Induced by Pulsed Laser Irradiation with Thin Metal. Open Journal of Fluid Dynamics, 6, 166-181. doi: 10.4236/ojfd.2016.63014.