Fluctuation of Void Fraction and Pressure Drop of Two-Phase Flow through a Vertical Pipe with Contraction

An adiabatic experiment was conducted to investigate the effect of channel geometry on gas-liquid two-phase flow characteristics in horizontal microchannels. A water-nitrogen gas mixture was pumped through a 96 μm square microchannel and the resulting flow pattern, void fraction and frictional pressure drop data were compared with those previously reported by the authors for a 100 μm circular microchannel. The pressure drop data were best estimated using a separated-flow model and the void fraction increased non-linearly with volumetric quality, regardless of the channel shape. However, the flow maps exhibited transition boundaries that were shifted depending on the channel shape.

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INVESTIGATION ON VOID FRACTION FOR TWO-PHASE FLOW PRESSURE DROP OF EVAPORATIVE R-290 IN HORIZONTAL TUBE

Jurnal Teknologi ◽

10.11113/jt.v78.9590 ◽

2016 ◽

Vol 78 (8-4) ◽

Cited By ~ 1

Author(s):

Agus Sunjarianto Pamitran ◽

Sentot Novianto ◽

Normah Mohd-Ghazali ◽

Nasruddin Nasruddin ◽

Raldi Koestoer

Keyword(s):

Pressure Drop ◽

Void Fraction ◽

Two Phase Flow ◽

Flow Boiling ◽

Homogeneous Model ◽

Saturation Temperature ◽

Horizontal Tube ◽

Phase Flow ◽

Two Phase ◽

Experimental Conditions

Two-phase flow boiling pressure drop experiment was conducted to observe its characteristics and to develop a new correlation of void fraction based on the separated model. Investigation is completed on the natural refrigerant R-290 (propane) in a horizontal circular tube with a 7.6 mm inner diameter under experimental conditions of 3.7 to 9.6 °C saturation temperature, 10 to 25 kW/m2 heat flux, and 185 to 445 kg/m2s mass flux. The present experimental data was used to obtain the calculated void fraction which then was compared to the predicted void fraction with 31 existing correlations. A new void fraction correlation for predicting two-phase flow boiling pressure drop, as a function of Reynolds numbers, was proposed. The measured pressure drop was compared to the predicted pressure drop with some existing pressure drop models that use the newly developed void fraction model. The homogeneous model of void fraction showed the best prediction with 2% deviation

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Modelling the pressure drop of two-phase flow through solid porous media

International Journal of Multiphase Flow ◽

10.1016/j.ijmultiphaseflow.2018.12.005 ◽

2019 ◽

Vol 112 ◽

pp. 13-26

Author(s):

Sonja Weise ◽

Sebastian Meinicke ◽

Thomas Wetzel ◽

Benjamin Dietrich

Keyword(s):

Porous Media ◽

Pressure Drop ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Flow Through

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Experimental Investigation on Flow Patterns and Frictional Pressure Drop of Downward Air-Water Two-Phase Flow in Vertical Pipes

Volume 2: Heat Transfer Enhancement for Practical Applications; Heat and Mass Transfer in Fire and Combustion; Heat Transfer in Multiphase Systems; Heat and Mass Transfer in Biotechnology ◽

10.1115/ht2013-17230 ◽

2013 ◽

Author(s):

Yuqing Xue ◽

Huixiong Li ◽

Tianyou Sheng ◽

Changjiang Liao

Keyword(s):

Pressure Drop ◽

Flow Pattern ◽

Oil Recovery ◽

Two Phase Flow ◽

Flow Patterns ◽

Phase Flow ◽

Vertical Pipe ◽

Two Phase Flows ◽

Two Phase ◽

Frictional Pressure Drop

A large amount of air need be transported into the reservoir in the deep stratum to supply oxygen to some microbes in Microbial Enhanced Oil Recovery (MEOR). Air-water two-phase flows downward along vertical pipeline during the air transportation. Base on the experiment data described in this paper, the characteristics of air-water two phase flow patterns were investigated. The flow pattern map of air-water two phase flows in the pipe with inner diameter of 65 mm was drawn, criterions of flow pattern transition were discussed, and the dynamic signals of the pressure and the differential pressure of the two phase flow were recorded to characterize the three basic flow regimes indirectly. The frictional pressure drop of downward flow in vertical pipe must not be disregarded contrast with upward two phase flow in the vertical pipe because the buoyancy must be overcame when the gas flows downward along pipe, and there would be a maximum value of frictional when the flow pattern translated from slug flow to churn flow.

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