Effect of surface wettability on flow characteristics in vertical upward gas-liquid two-phase flow

被引：0

作者：

Fuculty of Marine Technology, Tokyo University of Marine Science and Technology, 2-1-6 Etchujima, Koto-ku, Tokyo, 135-8533, Japan ^{[1
]}

机构：

[1] Fuculty of Marine Technology, Tokyo University of Marine Science and Technology, Koto-ku, Tokyo, 135-8533

来源：

Nihon Kikai Gakkai Ronbunshu, B | 2007年 / 7卷 / 1502-1509期

关键词：

Contact angle; Flow patterns; Flow visualization; Gas-liquid two-phase flow; Pressure drop; Void fraction; Wettability;

D O I：

10.1299/kikaib.73.1502

中图分类号：

学科分类号：

摘要：

To evaluate the effect of pipe wall surface wettability on flow characteristics in a vertical upward gas-liqid two-phase flow, a visualization study was performed using three test pipes : an acrylic pipe, a hydrophilic pipe and a hydrophobic pipe. Such basic flow characteristics as flow patterns, pressure drop and void fraction were investigated in these three pipes. In the hydrophilic pipe, the slug flow to churn flow transition boundary was shifted to a higher gas velocity at a given liquid velocity, whereas the churn flow to annular flow transition boundary was shifted to a lower gas velocity at a given liquid velocity. In the hydrophobic pipe, an inverted churn flow regime was observed in the region where the churn flow regime was observed in the acrylic pipe, while a droplet flow regime was observed in the region where an annular flow regime was observed in the acrylic pipe. At a high gas flow rate, the mean void fraction in the hydrophobic pipe was higher than in the acrylic pipe. The effect of surface wettability on frictional pressure loss was confirmed to be insignificant under the present experimental conditions.

引用

页码：1502 / 1509

页数：7

共 14 条

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