| Title |
Boiling Heat Transfer Characteristics of R-290in Horizontal Smooth Minichannel |
| Authors |
최광일 ; A.S. Pamitran ; 오종택 |
| Keywords |
Minichannel ; 미세관 ; R-290 ; 프로판 ; Flow boiling ; 흐름비등 ; Pressure gradient ; 압력강하 ; Heat transfer coefficient ; 열전달계수 ; Correlation ; 상관식 |
| Abstract |
The present paper dealt with an experimental study of boiling heat transfer characteristics of R-290. Pressure gradient and heat transfer coefficient of the refrigerant flow inside horizontal smooth minichannel were obtained with inner tube diameter of 3.0mm and length of 2,000mm. The direct electric heating method was applied for supplying a heat to the refrigerant uniformly. The experiments were conducted with R-290 purity of 99.99%, at saturation temperature of 0 to 10℃, a mass flux range of 50∼250kg/m2s, and a heat flux range of 5∼20kW/m2. The heat transfer coefficients of R-290 increased with increasing mass flux and saturation temperature, wherein the effect of mass flux was higher than that of the saturation temperature. Heat flux has a low effect on the increasing of heat transfer coefficient. The heat transfer coefficient was compared with six existing heat transfer coefficient correlations. The Zhang et al.'s correlation(2004) gave the best prediction of heat transfer coefficient. A new correlation to predict the two-phase flow heat transfer coefficient was developed based on the Chen correlation. The new correlation predicted the experimental data well with a mean deviation of 11.78% and average deviation of －0.07%. |