EXPERIMENTAL INVESTIGATIONS ON BUBBLY FLOWS IN A STRAIGHT CHANNEL ROTATED AROUND AN AXIS PERPENDICULAR TO THE CHANNEL

This paper describes experimental investigations on the behavior of an air-water two-phase mixture in a horizontal, radial-flow and square-s ectioned straight channel, which rotates around an axis perpendicular to the channel. The hydraulic loss of head and the distributions of pr essures and void fractions in the channel were measured mainly in a bu bbly flow regime, and the effects of the rotating speed of the channel and the flow rate of water on the loss were discussed in relation to the inlet void fraction. When the rotating speed is increased or the f low rate of water is decreased, a predominant region of high void frac tions appearing on the downstream negative side tends to expand upstre am as the Rossby number is increased. An almost imperceptible pressure rise in the radial direction of this region causes an excessive incre ase in the hydraulic loss.