Erratum to “New prediction methods for CO2 evaporation inside tubes: Part I – A two-phase flow pattern map and a flow pattern based phenomenological model for two-phase flow frictional pressure drops” [Int. J. Heat Mass Transfer 51 (1–2) (2008) 111–124]

This paper presents a state-of-the-art review of the hydrodynamic aspects of two-phase flow across horizontal tube bundles. The review covers studies related to the evaluation of void fraction, two-phase flow behaviors and pressure drops on the shell side of staggered and in-line tube bundles for upward, downward and side-to-side flows. This study of the literature critically describes the proposed flow pattern maps and semi-empirical correlations for predicting void fraction and frictional pressure drop. These predicting methods are generally based on experimental results for adiabatic air-water flows. A limited number of experimental studies with R-11 and R-113 were also carried out in the past. The review shows noticeable discrepancies among the available prediction methods. Finally, this study suggests that further research focusing on the development of representative databanks and new prediction methods is still necessary.

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Development of a diabatic two-phase flow pattern map for horizontal flow boiling

International Journal of Heat and Mass Transfer ◽

10.1016/s0017-9310(01)00146-6 ◽

2002 ◽

Vol 45 (2) ◽

pp. 291-301 ◽

Cited By ~ 42

Author(s):

O. Zürcher ◽

D. Favrat ◽

J.R. Thome

Keyword(s):

Flow Pattern ◽

Two Phase Flow ◽

Flow Boiling ◽

Horizontal Flow ◽

Phase Flow ◽

Two Phase ◽

Flow Pattern Map

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Flow Boiling in Horizontal Tubes: Part 1—Development of a Diabatic Two-Phase Flow Pattern Map

Journal of Heat Transfer ◽

10.1115/1.2830037 ◽

1998 ◽

Vol 120 (1) ◽

pp. 140-147 ◽

Cited By ~ 263

Author(s):

N. Kattan ◽

J. R. Thome ◽

D. Favrat

Keyword(s):

Flow Pattern ◽

Two Phase Flow ◽

Flow Boiling ◽

Phase Flow ◽

Two Phase ◽

Flow Parameters ◽

Horizontal Tubes ◽

Flow Pattern Map ◽

Wide Range ◽

Data Points

An improved two-phase flow pattern map is proposed for evaporation in horizontal tubes. The new map was developed based on flow pattern data for five different refrigerants covering a wide range of mass velocities and vapor qualities. The new map is valid for both adiabatic and diabatic (evaporating) flows and accurately identifies about 96 percent of the 702 data points. In addition, the new flow pattern map includes the prediction of the onset of dryout at the top of the tube during evaporation inside horizontal tubes as a function of heat flux and flow parameters.

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Flow Characteristics and Frictional Pressure Drops of Gas-Liquid Two-Phase Flow in Mini-Micro Pipes and at Vena Contract and Expansion

ASME 5th International Conference on Nanochannels, Microchannels, and Minichannels ◽

10.1115/icnmm2007-30198 ◽

2007 ◽

Author(s):

Hiroyasu Ohtake ◽

Hideyasu Ohtaki ◽

Yasuo Koizumi

Keyword(s):

Pressure Drop ◽

Flow Pattern ◽

Two Phase Flow ◽

Liquid Velocity ◽

Flow Patterns ◽

Experimental Results ◽

Phase Flow ◽

Two Phase ◽

Pressure Drops ◽

Frictional Pressure Drop

The frictional pressure drops and two-phase flow patterns of gas-liquid two-phase flow in mini-micro pipes and at vena contract and expansion were investigated experimentally. Test liquid was water; test gas was argon. The diameter of the test mini-pipe was 0.5, 0.25 and 0.12 mm, respectively. The pressure drop data and the flow pattern were collected over 2.1 < Ug < 92.5 m/s for the superficial gas velocity and 0.03 < Ul < 10 m/s for the superficial liquid velocity. The experimental results show that the flow patterns were slug, churn, ring and annular flows; pure bubbly flow pattern was not observed in a range of the present experimental conditions. The two-phase friction multiplier data for D > 0.5 mm showed to be in good agreement with the conventional correlations. On the other hand, the two-phase friction multiplier data for D < 0.25 mm differed from the calculated values by the conventional correlations. Then, thickness of liquid film around a gas plug and size of gas core were estimated and the effect of frictional pressure drop on channel size was discussed through Knudsen Number of gas and instability on liquid-gas interface. The coefficients of sudden enlargement and sudden contraction in mini-pipes for the gas-water two-phase flow were modified from the present experimental results.

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