نوع مقاله : مقاله پژوهشی
نویسندگان
1 کارشناسی ارشد،دانشگاه صنعتی مالک اشتر، تهران، ایران
2 استادیار، دانشگاه صنعتی مالک اشتر، تهران، ایران
3 دانشیار، دانشگاه صنعتی مالک اشتر، تهران، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
In this research, the numerical analysis of the flow structure and two-phase heat transfer in micro-channels with hydraulic diameters of 0.55 and 0.7 mm has been investigated. For this purpose, Fluent software was used and programming was done to model the phase change in this software. The inlet flow is assumed to be supersaturated vapor of R134A refrigerant at different mass fluxes at the entrance of the microchannel and the wall of the microchannel is considered as a constant flux. The effect of the geometrical shape of the cross-section of the micro-channel in 3 geometries of circular, square and trapezoidal cross-section in the input mass flux range of 〖kg/(m〗^2 s) 100-600 on the heat transfer coefficient and pressure drop has been evaluated. The results show that under the same conditions of the inlet mass flux and the cross-sectional area of the microchannel, the heat transfer coefficient in the microchannel with a hydraulic diameter of 0.55 mm is about 15% higher. Also, in a certain range of the input mass flux, the pressure drop in the hydraulic diameter of 0.55 mm is about 3 times the pressure drop in the hydraulic diameter of 0.7 mm. In both hydraulic diameters of 0.55 and 0.7 mm, square, circular and trapezoidal microchannels had the highest heat transfer coefficient, respectively.
کلیدواژهها [English]
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