Lateral motion and departure of vapor bubbles in nucleate pool boiling on thin wires in microgravity
A space experiment on bubble behavior and heat transfer in subcooled pool boiling phe-nomenon has been performed utilizing the temperature-controlled pool boiling (TCPB) device bothin normal gravity in the laboratory and in microgravity aboard the 22 nd Chinese recoverable satellite.The uid is R113 at 0.1MPa and subcooled by 26C nominally. A thin platinum wire of 60μm indiameter and 30mm in length is simultaneously used as heater and thermometer. Only the lateralmotion and the departure of discrete vapor bubbles in nucleate pool boiling are reported and analyzedin the present paper. A scale analysis on the Marangoni convection surrounding a bubble in the pro-cess of subcooled nucleate pool boiling leads to formulas of the characteristic velocity of the lateralmotion and its observability. The predictions consist with the experimental observations. Consideringthe Marangoni effect, a new qualitative model is proposed to reveal the mechanism underlying thebubble departure processes and a quantitative agreement can also be acquired.
microgravity nucleate pool boiling lateral motion bubble departure diameter Marangoni effect
J.F.Zhao S.X.Wan G.Liu Z.D.Li Y.H.Lu N.Yan
National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences.Beijing 100080, China
国际会议
The Fifth International Conference on Fluid Mechanics(第五届国际流体力学会议)
上海
英文
2007-08-15(万方平台首次上网日期,不代表论文的发表时间)