A balloon bursting underwater

Abstract

A buoyant vortex ring produced by an underwater bursting balloon was studied experimentally. The effect of dimensionless surface tension on characteristics including rise velocity, rate of expansion, circulation, trajectory, and lifetime of the vortex ring bubble was investigated. Results showed reasonable agreement with the literature on vortex rings produced by conventional approaches. It was observed that as the dimensionless surface tension increased, the rise velocity, the circulation and consequently the stability of the vortex ring bubble increased; however, the rate of expansion tends toward constant values. A semi-analytical model is proposed by modifying the drag-based model presented by Sullivan et al. (J. Fluid Mech., vol. 609, 2008, pp. 319-347) to make it applicable to buoyant vortex rings. The modified model suggests that the vortex ring expansion is essentially due to the buoyancy force. An expression is also derived for the circulation in terms of the initial volume of the balloon and the depth at which the balloon bursts.

A review of marine renewable energy storage

“…Currently, there is still a shortage of studies on this safety issue. Based on the UWCAES with flexible air accumulators, Vasel‐Be‐Hagh et al studied the production and the development of a buoyant vortex ring generated by an underwater bursting balloon. In order to mitigate the potential hazard of large‐scale vortex rings and air bubbles caused by the broken underwater air accumulators, Lewis et al proposed a method to fragment the big bubbles into a plurality of fragmented bubbles by maintaining a grid disposed between the air accumulators and the water surface.With the increasing maturity of the marine engineering technologies and various CAES technologies, and the increasing demand of the MRE and energy storage, UWCAES is being realized commercially.…”

“…Currently, there is still a shortage of studies on this safety issue. Based on the UWCAES with flexible air accumulators, Vasel-Be-Hagh et al 168 studied the production and the development of a buoyant vortex ring generated by an underwater bursting balloon. In order to mitigate the potential hazard of large-scale vortex rings and air bubbles caused by the broken underwater air accumulators, Lewis et al 169 79,154,161,[170][171][172][173][174][175] Hydrostor is presently the leader in this field.…”

Determination of the Parameters of a Vortex Ring with an Air Core in a Liquid by Computer Processing of Video Images

“…It should be noted that such inhomogeneity is a typical phenomenon for experiments with large air cores. In the photograph presented in [14,15], the shape of the bubble core is also inhomogeneous in space. However, the method for measuring the vortex parameters is not described there.…”

Spreading rate of a toroidal air bubble in water

“…Toroidal bubbles are a species of vortex rings [1] buoyant in liquid, in which gas is used as the buoyant matter [2][3][4][5][6]. Their characteristic feature is that the gas concentrates under the centrifugal force in the vicinity of the vortex ring core axis over the entire period of motion.…”