Micro-Bubbly Flows in Rotating Pipe Sections with Abrupt Expansion and Contraction

Abstract

An investigation was carried out for swirling flow in a rotating pipe with highly viscous fluid containing micro-bubbles experimentally and numerically. In the numerical analysis, bubble trajectory of each bubble was calculated using resultant numerical flow field solutions. From experimental results, with an aid of the numerical simulation, data were obtained for the location of a stagnation point, which moves towards the inlet region as swirl ratio being increased. It was found that the position of the stagnation point had a particular convergence value in relation with Reynolds number and types of the rotating channel. In the bubble behavior, big bubbles fall into the stagnation point, and that the parabolic surface is formed by some smaller bubbles. Critical diameter of bubble, which was to be caught at the stagnation point, was also obtained numerically for the model rotating channels.

Experimental Study of Pumping Performance of Rotating Helical Pump as a Gas—Liquid Transporter

“…The cost of such transportation is high, and there is a demand for the new technology of multi-phase transportation, which can reduce the cost by eliminating separation equipment and extra pipelines [1,2]. In contrast, if multi-phase transporters are not used, separation of the mixture and also elimination of bubbles in some fluid systems operating in industry or medical science are strongly required [3].…”