Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels(TWFC) were established with structural parameters of fins considered.The air side properties of heat transfe...Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels(TWFC) were established with structural parameters of fins considered.The air side properties of heat transfer coefficient and pressure drop are displayed with variable structural parameters of fins and inlet velocities of cooling air.Within the range of simulation,TWFC has the best comprehensive performance when inlet velocity vin=4-10 m/s.Compared with those of straight fins,the simulation results reveal that the triangular wavy fin channels are of higher heat transfer performances especially with the fin structural parameters of fin-height Fh=9.0 mm,fin-pitch Fp=2.5-3.0 mm,fin-wavelength λ=14.0-17.5 mm and fin-wave-amplitude A=1.0-1.2 mm.The correlations of both heat transfer factor and friction factor are presented,and the deviations from the experimental measurements are within 20%.展开更多
Single phase heat transfer analysis of water and R134a refrigerant （liquid phase） has been carried out using CFD （Computational fluid dynamics） approach for rectangular channel with smooth wavy fin. Colburnj facto...Single phase heat transfer analysis of water and R134a refrigerant （liquid phase） has been carried out using CFD （Computational fluid dynamics） approach for rectangular channel with smooth wavy fin. Colburnj factor and Fanning friction factorf are predicted for wavy fin. The correlations are developed at Reynolds number range of 100-15,000. The effect of fin geometry （fin spacing, fin height, wave height and wave length） on the enhanced heat transfer and pressure drops are investigated. Results show that there is no significant variation off factor for water and liquid R134a at constant Reynolds number. However variations inj factor were observed at constant Reynolds number. Colburnj factor and Fanning friction factorfcorrelations are proposed in terms of Re and geometry parameters （h/s, a/s, L/a） for water and liquid refrigerant R134a in the present study. Two separate equations are proposed for the low and high Re regions i.e. between Re of 100-1,000 and Re of 1,000-15,000.展开更多
基金Project(50976022) supported by the National Natural Science Foundation of ChinaProject(BY2011155) supported by the Provincial Science and Technology Innovation and Transformation of Achievements of Special Fund Project of Jiangsu Province,China
文摘Numerical computation models of air cooling heat transfer and flow behaviors in triangular wavy fin channels(TWFC) were established with structural parameters of fins considered.The air side properties of heat transfer coefficient and pressure drop are displayed with variable structural parameters of fins and inlet velocities of cooling air.Within the range of simulation,TWFC has the best comprehensive performance when inlet velocity vin=4-10 m/s.Compared with those of straight fins,the simulation results reveal that the triangular wavy fin channels are of higher heat transfer performances especially with the fin structural parameters of fin-height Fh=9.0 mm,fin-pitch Fp=2.5-3.0 mm,fin-wavelength λ=14.0-17.5 mm and fin-wave-amplitude A=1.0-1.2 mm.The correlations of both heat transfer factor and friction factor are presented,and the deviations from the experimental measurements are within 20%.
文摘Single phase heat transfer analysis of water and R134a refrigerant （liquid phase） has been carried out using CFD （Computational fluid dynamics） approach for rectangular channel with smooth wavy fin. Colburnj factor and Fanning friction factorf are predicted for wavy fin. The correlations are developed at Reynolds number range of 100-15,000. The effect of fin geometry （fin spacing, fin height, wave height and wave length） on the enhanced heat transfer and pressure drops are investigated. Results show that there is no significant variation off factor for water and liquid R134a at constant Reynolds number. However variations inj factor were observed at constant Reynolds number. Colburnj factor and Fanning friction factorfcorrelations are proposed in terms of Re and geometry parameters （h/s, a/s, L/a） for water and liquid refrigerant R134a in the present study. Two separate equations are proposed for the low and high Re regions i.e. between Re of 100-1,000 and Re of 1,000-15,000.
