窄通道内不凝结气体对过冷沸腾汽泡行为的影响
Effect of Dissolved Gas on Bubble Behavior of Subcooled Boiling in Narrow Channel
-
摘要: 针对窄通道内不凝结气体对过冷沸腾汽泡行为的影响进行了实验研究，通过高速摄影仪记录了矩形窄通道内含和不含不凝结气体的汽泡行为并进行了分析。分析结果表明：在过冷沸腾条件下不凝结气体对汽泡行为产生了较大的影响，延缓了汽泡的生长和冷凝，使汽泡的直径变化呈震荡特性；从蒸汽的产生和冷凝角度分析，不凝结气体的存在有利于汽泡的生存，促进了汽泡之间的聚合过程，在一定程度上有利于换热。Abstract: An experimental investigation was performed to study the effect of dissolved gas on bubble behavior in narrow rectangular channel under subcooled boiling condition. A high-speed digital video camera was applied to capture the dynamics of the bubble with or without dissolved gas in a narrow rectangular channel. It is found that the dissolved gas has great influence on bubble behavior in subcooled boiling condition. The dissolved gas slows down the rate of bubble growth and condensation and makes the variation of the bubble diameter present some oscillation characteristics. This phenomenon was discussed in the view of the vapor evaporation and condensation. The existence of the dissolved gas can facilitate the survival of the bubble and promote the aggregation of bubbles, and enhence heat transfer enhancement in some ways.
-
Keywords:
- bubble behavior ,
- dissolved gas ,
- narrow rectangular channel ,
- subcooled boiling
-
-
[1] CIONCOLINI A, SANTINI L, RICOTTI M E. Effects of dissolved air on subcooled and saturated flow boiling of water in a small diameter tube at low pressure[J]. Experimental Thermal and Fluid Science, 2007, 32(1): 38-51. [2] RAINEY K N, YOU S M, LEE S. Effect of pressure, subcooling and dissolved gas on pool boiling heat transfer from microporous, square pin-finned surfaces in FC-72[J]. International Journal of Heat and Mass Transfer, 2003, 46(1): 75-83. [3] STEINKE M E, KANDLIKAR S G. Control and effect of dissolved air in water during flow boiling in microchannels[J]. International Journal of Heat and Mass Transfer, 2004, 47(8/9): 1925-1935. [4] ADAMS T M, GHIAASIAAN S M, ABDEL-KHALIK S I. Enhancement of liquid forced convection heat transfer in microchannels due to the release of dissolved noncondensables[J]. International Journal of Heat and Mass Transfer, 1999, 42(19): 3563-3573. [5] LI J, PETERSON G P. Microscale heterogeneous boiling on smooth surfaces-from bubble nucleation to bubble dynamics[J]. International Journal of Heat and Mass Transfer, 2005, 48(21-22): 4316-4332. [6] PRODANOVIC V. Bubble behavior in subcooled flow boiling at low pressures and flow rates[D]. Canada: The University of British Columbia, 2001.
计量
- 文章访问数: 340
- HTML全文浏览量: 0
- PDF下载量: 1209
下载:
