Abstract
Zigzag rising motion of a bubble is a typical motion of bubbles in bubbly flows. The vortices shed oscillatory behind a bubble and its wake turned periodically like a sign of inequality are regarded as the most fundamental causes to change bubbly flows turbulent, because these phenomena produce the alternate lift force based on both conservation laws of circulation and momentum, respectively. In the present paper, we discuss the lift production on a zigzag rising bubble trailing a hairpin vortex by means of a spinning sphere model which is constructed by us to hold the aerodynamic universality independent on Reynolds number. We explicated fluid-dynamically the phenomenon of the alternate lift production on a rising bubble in spinless and the zigzag turning of its path, and we propose a chain of processes mentioned in the present paper as a fluid-dynamic mechanism which makes a rising bubble zigzag motion.
