以空气和水为实验工质,分别在40mm×1.6mm和40mm×3mm的矩形通道中对竖直向上气一液两相流动阻力特性进行了实验研究。该研究还对比了现有的两相流动阻力计算关系式,结果表明,对于窄缝为1.6mm的通道,传统的阻力计算关系式均不适用;而窄缝为3mm的通道,除Friedel模型和Tran模型外,其余模型与实验值符合较好。为此结合实验数据,以分液相雷诺数为依据将流动分为层流区、过渡区和湍流区3个区域,分别对Chisholm关系式进行修正,结果表明:C为当量直径的线性函数,当量直径越大,C越小。修正关系式与实验数据的误差较小,能很好地预测本次实验结果。
Two-phase frictional pressure drop gradients of air-water mixture were stud- ied in two vertical narrow rectangular ducts (40 mm× 1.6 mm and 40 mm× 3 mm). The experimental results show that the conventional correlations fail to predict the two-phase flow pressure drop in narrow rectangular duct with the 1.6 mm gap, but can predict the two-phase pressure gradient satisfactorily in rectangular duct with 3 mm gap except Friedel model and Tran model. Different modified Chisholm correlations were proposed in two regions which were distinguished by the liquid Reyonlds number. The results show that the constant C has a linear relationship with the hydraulic diameter, and C decreases with the increase of the hydraulic diameter. The new correlations gave accu- rate predictions of the pressure drop.