R1233zd(E)在非等宽并联微通道内的流动沸腾传热实验研究OA

The subcooled flow boiling heat transfer of R1233zd(E)in uniform-and variable-width parallel microchannels was investigated experimentally.The heat transfer characteristics of two channel structures were analyzed and compared under different subcooling,mass-flux,and heat-flux conditions.The experimental results reveal that the onset of nucleate boiling(ONB)of the variable-width parallel microchannel occurred earlier and that the wall temperature could be maintained at a lower value.In addition,the overall heat transfer characteristics of the variable-width microchannel were better than those of the uniform-width microchannel.When the mass flux was 1 263 kg/(m2·s),the wall superheat of the variable-width parallel microchannel was 3.2℃lower than that of the uniform-width parallel microchannel.When the heat flux was 150 kW/m2,the coefficient of heat transfer(HTC)of the variable-width parallel microchannel increased by 30%-50%compared with that of the uniform-width parallel microchannel.Moreover,the two-phase pressure drop in the variable-width parallel microchannels was higher than that in the uniform-width parallel microchannels,with a maximum increase of 61%.