Browsing by Author "Chiang, CS"

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An experimental study of in-tube evaporation of R-22 inside a 6.5-mm smooth tube
(1998-06-01)
Wang, CC
;
Chiang, CS
;
Yu, JG
;
機械工程學系
;
Department of Mechanical Engineering
Two-phase flow pattern, friction, and heat transfer characteristics for R-22 inside a 6.5 mm smooth tube are reported in this study. The range of mass flux is between 50 and 700 kg/m(2) s. The flow pattern map proposed by Weisman et al. (Weisman, J., Duncan, D., Gibson, J., Crawford, T., 1979. Effect of fluid properties and pipe diameter on two-phase flow pattern in horizontal lines. Int. J. Multiphase Flow 5, 437-462) gave a satisfactory flow pattern prediction, and the Klimenko and Fyodorov (Klimenko, V.V., Fyodorov, M., 1990. Prediction of heat transfer for two-phase forced flow in channels of different orientation. In: Proceedings of the Ninth International Heat Transfer Conference, vol. 6, pp. 65-70) criterion shows an excellent classification of the stratified and unstratified flow pattern. The two-phase multipliers are strongly related to the flow pattern, and it is found that the two-phase multiplier is dependent upon mass velocities for stratified-wavy flow pattern. In addition, the two-phase heat transfer coefficient for stratified-wavy flow pattern is found to be insensitive to the change of vapor quality, and is approximately proportional to q(0.6-0 7). (C) 1998 Elsevier Science Inc. All rights reserved.
Inversion MOS capacitance extraction for ultra-thin gate oxide using BSIM4
(2005)
Lee, W
;
Su, KW
;
Chiang, CS
;
Liu, S
;
Su, P
Two-phase heat transfer characteristics for R-22/R-407C in a 6.5-mm smooth tube
(1997-12-01)
Wang, CC
;
Chiang, CS
;
機械工程學系
;
Department of Mechanical Engineering
Two-phase friction and heat transfer characteristics for R-22/R-407C inside a 6.5-mm smooth tube are reported in this study, The hear transfer results for G = 100 and 400 kg/m(2) s were reported in the present study, and the adiabatic frictional pressure drop was recorded in the range of 100 to 700 kg/m(2) s, It is found that the development of flow pattern for R-407C Falls behind R-22. This may explain the lower pressure drops for R-407C. The major heat transfer mechanism at low mass flux is nucleate boiling, and virtually becomes the convective evaporation as mass flux increase to G = 400 krg/m(2) s, Meanwhile, the reduction of heat transfer coefficients for R-407C mixtures are especially profound at low mass flux, and The reduction of heat transfer coefficient decreases with the increase of mass flux. (C) 1997 by Elsevier Science Inc.
Two-phase heat transfer characteristics for R-22/R-407C in a 6.5-mm smooth tube
(1997-12-01)
Wang, CC
;
Chiang, CS
;
機械工程學系
;
Department of Mechanical Engineering
Two-phase friction and heat transfer characteristics for R-22/R-407C inside a 6.5-mm smooth tube are reported in this study, The hear transfer results for G = 100 and 400 kg/m(2) s were reported in the present study, and the adiabatic frictional pressure drop was recorded in the range of 100 to 700 kg/m(2) s, It is found that the development of flow pattern for R-407C Falls behind R-22. This may explain the lower pressure drops for R-407C. The major heat transfer mechanism at low mass flux is nucleate boiling, and virtually becomes the convective evaporation as mass flux increase to G = 400 krg/m(2) s, Meanwhile, the reduction of heat transfer coefficients for R-407C mixtures are especially profound at low mass flux, and The reduction of heat transfer coefficient decreases with the increase of mass flux. (C) 1997 by Elsevier Science Inc.
Visual observation of two-phase flow pattern of R-22, R-134a, and R-407C in a 6.5-mm smooth tube
(1997-11-01)
Wang, CC
;
Chiang, CS
;
Lu, DC
;
機械工程學系
;
Department of Mechanical Engineering
Two-phase flow pattern and friction characteristics for R-22, R-134a, and R-407C inside a 6.5 mm smooth tube are reported in this study. The range of mass flux is between 50 and 700 kg/(m(2) s). The experimental data show that the two-phase friction multipliers are strongly related to the flow pattern. For a stratified, wavy flow pattern a mass-flux dependence of the multipliers is seen. The flow pattern transition for the mixture refrigerant shows a considerable delay, compared with that of pure refrigerant. (C) Elsevier Science Inc., 1997.