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Title: Vertical two-phase flow regimes and pressure gradients: Effect of viscosity

Abstract

The effect of liquid viscosity on the flow regimes and the corresponding pressure gradients along the vertical two-phase flow was investigated. Experiment was carried out in a vertical transparent tube of 0.019 m in diameter and 3 m in length and the pressure gradients were measured by a U-tube manometer. Water and a 50 vol.% glycerol solution were used as the working fluids whose kinematic viscosities were 0.85 x 10{sup -6} and 4.0 x 10{sup -6} m{sup 2}/s, respectively. In our air-liquid annular two-phase flow, the liquid film of various thicknesses flowed adjacent to the wall and the gas phase flowed at the center of the tube. The superficial air velocity, j{sub air}, was varied between 0.0021 and 58.7 m/s and the superficial liquid velocity, j{sub liquid}, was varied between 0 and 0.1053 m/s. In the bubble, the slug and the slug-churn flow regimes, the pressure gradients decreased with increasing Reynolds number. But in the annular and the mist flow regimes, pressure gradients increased with increasing Reynolds number. Finally, the experimentally measured pressure gradient values were compared and are in good agreement with the theoretical values. (author)

Authors:
; ;  [1];  [2]
  1. The Petroleum and Petrochemical College, Chulalongkorn University, Soi Chula 12, Phayathai Road, Pathumwan, Bangkok 10330 (Thailand)
  2. Department of Chemical Engineering, The University of Michigan, Ann Arbor, MI 48109-2136 (United States)
Publication Date:
OSTI Identifier:
20880658
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 31; Journal Issue: 6; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; TWO-PHASE FLOW; LIQUIDS; PRESSURE GRADIENTS; REYNOLDS NUMBER; AIR; VISCOSITY; SOLUTIONS; GLYCEROL; WATER; VELOCITY; TUBES; THICKNESS; FILMS; BUBBLES

Citation Formats

Da Hlaing, Nan, Sirivat, Anuvat, Siemanond, Kitipat, and Wilkes, James O. Vertical two-phase flow regimes and pressure gradients: Effect of viscosity. United States: N. p., 2007. Web. doi:10.1016/J.EXPTHERMFLUSCI.2006.03.030.
Da Hlaing, Nan, Sirivat, Anuvat, Siemanond, Kitipat, & Wilkes, James O. Vertical two-phase flow regimes and pressure gradients: Effect of viscosity. United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.03.030.
Da Hlaing, Nan, Sirivat, Anuvat, Siemanond, Kitipat, and Wilkes, James O. Tue . "Vertical two-phase flow regimes and pressure gradients: Effect of viscosity". United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.03.030.
@article{osti_20880658,
title = {Vertical two-phase flow regimes and pressure gradients: Effect of viscosity},
author = {Da Hlaing, Nan and Sirivat, Anuvat and Siemanond, Kitipat and Wilkes, James O.},
abstractNote = {The effect of liquid viscosity on the flow regimes and the corresponding pressure gradients along the vertical two-phase flow was investigated. Experiment was carried out in a vertical transparent tube of 0.019 m in diameter and 3 m in length and the pressure gradients were measured by a U-tube manometer. Water and a 50 vol.% glycerol solution were used as the working fluids whose kinematic viscosities were 0.85 x 10{sup -6} and 4.0 x 10{sup -6} m{sup 2}/s, respectively. In our air-liquid annular two-phase flow, the liquid film of various thicknesses flowed adjacent to the wall and the gas phase flowed at the center of the tube. The superficial air velocity, j{sub air}, was varied between 0.0021 and 58.7 m/s and the superficial liquid velocity, j{sub liquid}, was varied between 0 and 0.1053 m/s. In the bubble, the slug and the slug-churn flow regimes, the pressure gradients decreased with increasing Reynolds number. But in the annular and the mist flow regimes, pressure gradients increased with increasing Reynolds number. Finally, the experimentally measured pressure gradient values were compared and are in good agreement with the theoretical values. (author)},
doi = {10.1016/J.EXPTHERMFLUSCI.2006.03.030},
journal = {Experimental Thermal and Fluid Science},
number = 6,
volume = 31,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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