Abstract: The heat transfer characteristics in microchannel 0.86 mm in diameter for refrigerant mixture R32/R134a with three different mass proportions were studied and the effect of non-azeotropic working media with different mass proportions on heart transfer in the microchannel was investigated. The experiment result showed that when mass proportion was 35%/65%，flow boiling heat transfer was the best at low dryness fraction，while the effect of mass proportion on heat transfer was not obvious at high dryness fraction. Heat transfer resistance effect was not obvious at a high mass flux. Pressure drop was the largest when mass proportion was 15%/85%，and for the other two mass proportions，25%/75% and 35%/65%，pressure drop was relatively smaller.

Key words: flow boiling, non-azeotropic, proportion, microchannel

摘要： 采用了3种不同组分比例的R32/R134a工质在0.86 mm的微通道中进行了传热特性和阻力特性的实验研究，考察了非共沸工质不同组分比例对微通道换热特性的影响。实验结果表明：在组分质量分数比为35%/65%时，核态沸腾在小干度下换热效果最好；干度较大时，组分比例对换热的影响效果降低。在大质量流量下传热阻力效应的影响不再明显。在压降方面，组分比为15%/85%的相对压降最大，其它两种组分的压降较小。

关键词: 流动沸腾, 非共沸, 组分比, 微通道