摇摆状态下竖直管内环状流摩擦压降计算

对摇摆状态下3种不同管径的竖直管管内环状流摩擦压降计算进行了研究.以分相流模型为基础,对采用传统奇斯霍姆常数C所得到的环状流摩擦压降计算值与实验值进行比较,发现误差很大.通过分析发现,在摇摆状态下,奇斯霍姆常数C与滑速比呈降幂指数关系.结合实验数据给出了相应的计算关系式,并采用该计算式对环状流摩擦压降进行计算,实验值与计算值符合较好.

Calculation of Frictional Pressure Drop of Annular Flow in Rolling Vertical Tubes

The calculation of the pressure drop of annular flow in rolling vertical tubes with three different diameters was studied. Based on separated flow model, it was found that calculations of annular flow frictional pressure drop with conventional Chisholm C-value were higher than the experimental data. Through the analysis, the Chisholm C-value under rolling condition was shown to decline exponent with the increase of slip ratio, then the correlation for C-value under rolling condition was proposed on the basis of the experimental data. Applying the new proposed correlation for C-value to separated flow model, it was shown that the calculations of annular flow frictional pressure drop correlated well with experimental data.