Experimental Study of Spark Channel Expansion in Water

The prime objective of this article is to determine the accuracy of prediction of underwater spark expansion using an incompressible approach. A spark channel expansion is studied experimentally using a high-speed camera and an optical hydrophone. The experimental results are compared with solutions to three sets of mathematical equations for incompressible liquids. A detailed comparison between these numerical simulations and the experimental results shows the existence of a strict limit of applicability of the incompressible approximation. However, within this limit, a mathematical description using the incompressible approach provides reasonable agreement with the experimental results.