Evaluation of vortex gas entrainment phenomena

Ito, Kei*; Matsushita, Kentaro  ; Ezure, Toshiki ; Tanaka, Masaaki  ; Odaira, Naoya*; Ito, Daisuke*; Saito, Yasushi*

The estimation of entrained gas flow rate by a bathtub vortex is important in terms of a possibility to causes the performance degradation when the entrained bubbles are mixed into fluid machineries, e.g. pumps. In this study, to confirm the applicability of a model based on circulating annular flow model proposed by the authors, entrained gas flow rate is evaluated using the liquid velocity distribution around free surface dent of vortex (gas core), obtained by CFD data. As a result, it was indicated that it would be possible to evaluate the gas entrainment flow rate by setting an appropriate evaluation region.