Measurement of Bubble Plume Generated Surface Flow Using PIV

Abstract

Bubble plume is known as one of transport phenomena which drive a large scale natural convection due to buoyancy of bubbles. Surface flow generated by the bubble plume is utilized for protecting naval systems, rivers, and lakes. In the past, however, the detailed mechanism of the surface flow generation process has not been measured experimentally. This paper reports the characteristics of the surface flow which depends on the gas flow rate, the bubble size, and the internal two-phase flow structure of the bubble plume. The data are obtained by applying particle imaging velocimetry (PIV) to three kinds of visualized images; the first is visualization of the whole field around the bubble plume, the second that of the upper view of the surface flow, and the third that of the surface flow generation region under the free surface. As an additional function of the surface flow, the wave-damping effects are also discussed.