Modelling of an Influence of Liquid Velocity Above the Needle on the Bubble Departures Process

In the present paper, the influence of liquid flow above the needle on a periodic or chaotic nature of the bubble departures process was numerically investigated. During the numerical simulations bubbles departing from the needle was considered. The perturbations of liquid flow were simulated based on the results of experimental investigations described in the paper [1]. The numerical model contains a bubble growth process and a liquid penetration into a needle process. In order to identify the influence of liquid flow above the needle on a periodic or chaotic nature of bubble departures process, the methods data analysis: wavelet decomposition and FFT were used. It can be inferred that the bubble departure process can be regulated by altering the hydrodynamic conditions above the needle, as variations in the liquid velocity in this area affect the gas supply system’s conditions. Moreover, the results of numerical investigations were compared with the results of experimental investigation which are described in the paper [2]. It can be considered that, described in this paper, the numerical model can be used to study the interaction between the bubbles and the needle system for supplying gas during the bubble departures from two needles, because the interaction between the bubbles is related to disturbances in the liquid flow above the needle.