The chaotic bubble departures as Aresult of nonlinearity of gas compression in the plenum

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.

In the paper it has been analysed the influence of: nozzle diameter and height of liquid over the nozzle on the chaotic character of bubble departures. The analysis has been conducted based on the numerical model of chaotic bubble departures proposed in the paper [3]. The following forces in the model of bubble growth have been considered: drag force, Boussinesq–Basset force, added-mass forces and the changes in the gas momentum. The influence of Boussinesq–Basset and added-mass forces on the frequency of bubble departures has been discussed. It has been shown that the intensity of appearance of the chaotic bubble departures is caused by increase in the nozzle diameter and height of liquid over the nozzle. The increase of the nozzle diameter causes the decrease of the bubble departure frequency and the depth of liquid penetration into the nozzle. It has also been shown that the increase of liquid height over the nozzle outlet modify the character of bubble departure. The increase of liquid height over the nozzle modify the frequency of bubble departure and depth of liquid penetration into the nozzle. Both forces: Boussinesq–Basset and added mass promote the bubble departures and decrease the depth of liquid penetration into the nozzle. The added mass force is greater than the Boussinesq–Basset force.