Effect of microchannel tube end-cut techniques on two-phase flow pressure drop - an experimentally validated general correlation

摘要

An experimentally validated correlation for contraction losses in microchannel headers is presented. Pressure losses were recorded over the entire range of qualities from 100% vapor to 100% liquid. In addition, the tests were conducted for five different refrigerant mass fluxes between 185 kg/m~2-s and 785 kg/m~2-s using three differnt end-cut techniques. More than 1100 data points were recorded to obtain a comprehensive understanding of the effects of mass flux and quality on minor pressure losses. The results show that many of the commonly used correlations for estimating two-phase pressure losses significantly underpredict the pressure losses found in compact microchannel tube headers.