摘要：The liquid film thickness is crucial for studying the thermal hydraulic mechanism of the annular flow region in helically coiled tubes (HCTs). This paper introduces a refined experimental study on the liquid film thickness of annular flow in HCTs, utilizing a newly developed liquid film sensor. The experimental results indicate that the smaller coil diameters and pitches result in thinner average liquid film thicknesses. The average liquid film thickness decreases with increasing superficial gas velocity and decreasing superficial liquid velocity. However, the liquid film thickness at different circumferential positions on the cross-section of the tube exhibits varying sensitivities to superficial gas and liquid velocities. The experimental data reveal that the existing typical correlation formula for the average liquid film thickness of annular flow in straight tubes does not apply to HCTs. Consequently, a new prediction model is proposed for the average liquid film thickness of the annular flow region in HCTs, based on the modified Froude number, modified Dean number, Ekman number, and Reynolds number. This model comprehensively incorporates the structural characteristics of HCTs and fluid properties, and its validity is verified through the utilization of available and current data in the literature.

关键字：Helically coiled tubes; Liquid film thickness; Gas-liquid annular flow; Prediction model; Circumferential asymmetry

ISSN号：0301-9322

卷、期、页：卷: 182

发表日期：2025-01-01

影响因子：0.000000

期刊分区（SCI为中科院分区）：二区

收录情况：SCI（科学引文索引印刷版）,SCIE（科学引文索引网络版）

发表期刊名称：INTERNATIONAL JOURNAL OF MULTIPHASE FLOW

参与作者：刘帅,刘莉,顾汉洋

第一作者：王科

论文类型：期刊论文

论文概要：刘帅,刘莉,顾汉洋,王科，Experimental and theoretical study on liquid film thickness of upward annular flow in helically coiled tubes，INTERNATIONAL JOURNAL OF MULTIPHASE FLOW，2025，卷: 182

论文题目：Experimental and theoretical study on liquid film thickness of upward annular flow in helically coiled tubes