The energy partition of underwater sparks

Abstract

Underwater sparks have long been used by the geophysical prospecting community as a source of intense low-frequency sound. While bubble hydrodynamic models are well developed, the mechanism of transferring energy from the thermal power input, through the various energy conversion channels, to the work done by the bubble has not been adequately studied. In this work an ab initio model of the bubble dynamics, including blackbody ablation, ionization, dissociation, and radiative transport, is developed. This model is a first step in enumerating the important physical mechanisms within bubbles generated by underwater sparks. The predictions of this model are compared with experimental results. Experimental work is still needed to validate the model, and to determine if and how model parameters related to actual physical parameters and measurable effects.