Shock wave focusing in water inside convergent structures

• Main Authors: C Wang, V Eliasson
• Format: Article
• Language: English
• Published: Multi-Science Publishing 2016-09-01
• Series: International Journal of Multiphysics
• Online Access: http://journal.multiphysics.org/index.php/IJM/article/view/208

Experiments on shock focusing in water-filled convergent structures have been performed. A shock wave in water is generated by means of a projectile, launched from a gas gun, which impacts a water-filled convergent structure. Two types of structures have been tested; a bulk material and a thin shell structure. The geometric shape of the convergent structures is given by a logarithmic spiral, and this particular shape is chosen because it maximizes the amount of energy reaching the focal region. High-speed schlieren photography is used to visualize the shock dynamics during the focusing event. Results show that the fluid-structure interaction between the thin shell structure and the shock wave in the water is different from that of a bulk structure; multiple reflections of the shock wave inside the thin shell are reflected back into the water, thus creating a wave train, which is not observed for shock focusing in a bulk material.