Simulating self-oscillations in a boiling flow of subcooled liquid in the channel

Abstract

Results of experimental and theoretical research of dynamics of boiling of highly subcooled ethanol in the ring channel under the conditions of pulsing heating of the interior wall are presented. In experiments with the vertical channel, pulsations of a vapor film on a heater wall, accompanied by pressure oscillations with growing amplitude (the self-oscillatory mode), were observed. The mathematical model, which describes the non stationary process of boiling of ethanol in the channel, is presented. Model takes into account pulsations of a vapor film, evaporation of overheated liquid on a heater wall and vapor condensation owing to a flow of highly subcooled liquid. In numerical calculations the conditions of development of self-oscillations owing to evaporation of the liquid getting on a hot wall in the course of pulsations of a vapor film are revealed. Results of calculations well agree with experimental data.