Author(s)

R. M. B. Teymouri & G. Ahmadi

Abstract

The jet formation through the oscillation of a bubble between a couple of parallel rigid walls was numerically investigated. The Navier-Stokes and energy equations accompanying with the proper constitutive relations were numerically solved to predict the flow and thermal conditions inside and outside the bubble. The volume of fluid method was incorporated to capture the bubble surface applying a piecewise linear interface reconstruction method. For the bubble to walls distances less than certain limits, the bubble underwent a necking process after reaching to its maximum volume. The necking process led to splitting of the bubble and the formation of a couple of round jets toward the walls. The velocity of each jet was higher than the velocity of a jet induced through the oscillation of a bubble near a single wall. Also it was found that keeping the position of one of the walls fixed, the velocity of the jet toward that wall increases with increasing the other wall distance from the bubble, up to a certain limit. These analyses were performed for several initial inside to outside pressure ratios of the bubble. The results can be used for increasing the performance of the devices for which the jet induced through the near wall bubble oscillation is applied. Keywords: oscillating bubble, wall, jet, VOF. Advances in Fluid Mechanics VIII 193 www.witpress.com, ISSN 1743-3533 (on-line) WIT Transactions on Engineering Sciences, Vol 69, © 2010 WIT Press doi:

Keywords

oscillating bubble, wall, jet, VOF