Based on the energy and heat conductivity equations
an expression considering slip flow and temperature jump for fully developed temperature distribution of circular microchannel is achieved by means of the counter solution. New expressions for calculation of temperature jump efficient and Nusselt number are derived under the condition of uniform heat flux boundary. The heat transfer characteristic and size effects are analyzed by calculating Nusselt number and heat transfer efficient. Simulation of heat transfer of pure water in circular microchannel is conducted and it is revealed that in the slip flow region the heat transfer efficient increases with the decreasing tube radius. The temperature jump efficient in the wall increases with the decreasing entrance distance. The conclusion is confirmed by the experiments.
关键词
Keywords
references
Morini G L. Single-phase convective heat transfer in microchannels: a review of experimental results[J].Int J Thermal Sci,2004, 43(7):631-651.
Owhaib W, Palm B. Experimental investigation of singlephase convective heat transfer in circular micro channels[J].Exp Thermal Fluid Science,2004, 28(2/3):105-110.
Morini G L.Viscous heating in liquid flows in micro-channels[J]. International Journal of Heat and Mass Transfer,2005, 48(17): 3637-3647.
Sparrow E M, Lin S H. Laminar heat transfer in tubes under slip-flow conditions[J]. Journal of Heat Transfer,1962,84(4):363-369.
Wu Peiyi, Little W A. Measurement of heat transfer characteristics of gas flow in fine channel heat exchanger used for microminiature refrigerators [J]. Cryogenics, 1984,24(8):415-421.
陈熙.动力论及其在传热与流动研究中的应用[M]. 北京:清华大学出版社,1996:204-220.
杨世铭,陶文铨.传热学[M].3版.北京: 高等教育出版社,1999:26-137.
Qu Weiling, Mala G M, Li Dongqing. Heat transfer for water flow in trapezoidal silicon microchannels[J]. International Journal of Heat and Mass Transfer, 2000, 43(21):3925-3936.