Gas-Liquid Two-Phase Flow in Hot Embossed Square Microchannels

An experimental study was conducted to investigate the characteristics of gas-liquid two-phase flow in 200 μm square microchannels thermoformed in polymer chips. Polymer microfluidic chips were replicated using hot embossing of poly(methyl methacrylate) (PMMA) with micromachined brass mold inserts. The thermoformed microchannels in polymer chips typically had greater surface roughnesses compared to microchannels etched in the silicon substrate. Two more different polymer chips, a direct micromachined PMMA chip and a chip hot embossed with a LIGA nickel mold insert, were fabricated to compare surface characteristics of the sidewalls and bottoms of fabricated microchannels. Deionized water and dry air were injected separately into the chips at superficial velocities of jL = 0.005 – 0.11 m/s for the liquid and jG = 0.003 – 16.67 m/s for the gas. Capillary bubbly, plug, plug-annular, annular, and dry flows were observed in the microchannels. Two-phase flow pattern maps and transitions between flow regimes were determined for fixed values of the homogeneous liquid fraction defined as βL = QL/(QL + QG) where QL and QG are the liquid and gas flow rates, and the liquid Weber number fraction defined as γL = WeL/(WeL + WeG) where WeL and WeG are the liquid and gas Weber number. The surface roughness in submicron range showed minor effect in comparison with the previous work in terms of the gas-liquid two-phase flow patterns and transitions between flow regimes. Dimensionless bubble sizes scaled by the width of observation microchannel were plotted against the homogeneous liquid fraction (βL). A scaling law for the bubble length developed for the previous work with T-junctions was applicable to the present work used the cross junction for generation of segmented flow. With a fixed value of the fitting parameter, scaling law showed a good agreement with the experimental data. Deviation of the scaled bubble length from predicted bubble length line and irregularity of bubble length with a fixed homogeneous liquid fraction increased with higher gas flow rates.

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Simultaneous gas and water flow in a damage-susceptible bedded argillaceous rock

Canadian Geotechnical Journal ◽

10.1139/cgj-2013-0457 ◽

2015 ◽

Vol 52 (1) ◽

pp. 18-32 ◽

Cited By ~ 17

Author(s):

T.S. Nguyen ◽

A.D. Le

Keyword(s):

Water Flow ◽

Gas Flow ◽

Two Phase Flow ◽

Gas Injection ◽

Injection Pressure ◽

Opalinus Clay ◽

Phase Flow ◽

Two Phase ◽

Flow Rates ◽

Inherent Anisotropy

A mathematical model that couples the governing and constitutive equations of two-phase flow and mechanical equilibrium has been developed to simulate gas injection tests for both laboratory- and field-scale experiments. The model takes into consideration the inherent anisotropy of sedimentary rocks due to bedding by including an anisotropic elastoplastic model for the mechanical process and using an anisotropic permeability tensor for the flow processes for both water and gas. The gas and water flow rates are assumed to follow Darcy’s law. The relative permeability of each phase and their respective degrees of saturation are represented by the Van Genuchten’s functions. We simulated laboratory and field gas injection experiments in Opalinus clay, a candidate geological formation for the geological disposal of radioactive wastes. The numerical results show good agreement with the experimental data measured in these tests in terms of two-phase flow regimes and hydromechanical response at various monitoring locations. Damage zones, either pre-existing due to excavation or induced by high gas injection pressure, are shown to clearly influence the gas flow rates and directions and would need special consideration in the design and safety assessment of the repository system.

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Experimental Investigation of Two-Phase Flow Patterns in a Vertical to Horizontal Bend Pipe Using Wire-Mesh Sensor

Revista de Chimie ◽

10.37358/rc.20.12.8383 ◽

2021 ◽

Vol 71 (12) ◽

pp. 18-33

Author(s):

Lokman A. Abdulkareem ◽

Veyan A. Musa ◽

Raid A. Mahmood ◽

Ezideen A. Hasso

Keyword(s):

Flow Pattern ◽

Gas Flow ◽

Two Phase Flow ◽

Flow Patterns ◽

Phase Flow ◽

Two Phase ◽

Horizontal Pipe ◽

Flow Rates ◽

Tomographic Images ◽

High Range

The air-water two-phase flow plays an important role in many applications of industry fields. Usually, a 90-degree bend is used to connect pipes for changing the direction of flow which influences the two-phase flow pattern. In this paper, the effect of 90-degree bend under different ranges of gas and liquid superficial velocities on the two-phase flow patterns in the horizontal pipe located after the bend was experimentally investigated, and then results were presented and compared in a two-phase flow pattern map. Also, tomographic images and probability density functions were used to capture the cross-section void fraction and its distribution for the two-phase flow patterns. The results revealed that at low liquid and gas flow rates, a stratified-wavy flow pattern was observed as a dominant flow pattern. While the wavy-annular and semiannular flow patterns were observed at a high range of gas flow rates in the horizontal pipe. The results also showed that at the high range of liquid flow rate, bubbly, plug, slug, stratified-wavy, and wavy-annular flow patterns were observed in the horizontal pipe when the gas flow increased. The tomographic images and probability density functions gave good agreement with the experimental observations and results.

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Characterisation of Air-Water Two-Phase Flow Using a Wire-Mesh Sensor

Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B ◽

10.1115/imece2011-62777 ◽

2011 ◽

Cited By ~ 1

Author(s):

Carlos E. F. do Amaral ◽

O´liver B. S. Scorsim ◽

Eduardo N. Santos ◽

Marco Jose´ da Silva ◽

Marco Germano Conte ◽

...

Keyword(s):

High Speed ◽

Gas Flow ◽

Two Phase Flow ◽

Flow Patterns ◽

Industrial Applications ◽

Wire Mesh ◽

Phase Flow ◽

Two Phase ◽

Flow Rates ◽

Piping Systems

Two phase flow occurs in many industrial applications, mainly in the transport of mixtures. Many patterns can be produced according to the liquid and gas flow rates. The identification of these patterns is very important in the design of piping systems and equipments. This work proposes an experimental study to identify multiphase flow patterns of water and air in horizontal pipes. The study was developed using an experimental circuit of 26 mm diameter and 9.2 m length pipe, at Thermal Sciences Lab (LACIT) at the Federal University of Technology - Parana´. To characterize the flow patterns, an intrusive mesh electrodes sensor was used, which allows the detailed visualization of the phases distribution. Tests were made using several experimental settings of water and gas flow rates. Measurements were compared to images obtained by high speed camera and the temporal void fraction series which were analyzed with the use of PDF and PSD functions, showing the singularities for each two-phase flow pattern.

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The influence of the Stokes and Archimedes forces on the stability of a two-phase flow

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2003.1.020 ◽

2003 ◽

Vol 3 ◽

pp. 266-270

Author(s):

B.H. Khudjuyerov ◽

I.A. Chuliev

Keyword(s):

Spectral Method ◽

Stability Region ◽

Gas Flow ◽

Two Phase Flow ◽

Solid Phase ◽

Stability Characteristic ◽

Phase Flow ◽

Two Phase ◽

The Stability

The problem of the stability of a two-phase flow is considered. The solution of the stability equations is performed by the spectral method using polynomials of Chebyshev. A decrease in the stability region gas flow with the addition of particles of the solid phase. The analysis influence on the stability characteristic of Stokes and Archimedes forces.

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Maximum Two-Phase Flow Rates of Sub-Cooled Nitrogen Through a Sharp-Edged Orifice

Advances in Cryogenic Engineering ◽

10.1007/978-1-4757-0208-8_39 ◽

1960 ◽

pp. 299-306

Author(s):

R. J. Simoneau

Keyword(s):

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Flow Rates

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Experimental, Numerical, and Statistical Investigation of Two Phase Flow in a Cylindrical Perforation Tunnel

10.1115/omae2021-62956 ◽

2021 ◽

Author(s):

Ekhwaiter Abobaker ◽

Abadelhalim Elsanoose ◽

Mohammad Azizur Rahman ◽

Faisal Khan ◽

Amer Aborig ◽

...

Keyword(s):

Numerical Simulation ◽

Steady State ◽

Statistical Analysis ◽

Flow Rate ◽

Gas Flow ◽

Two Phase Flow ◽

Phase Flow ◽

Gas Flow Rate ◽

Two Phase ◽

Flow Through

Abstract Perforation is the final stage in well completion that helps to connect reservoir formations to wellbores during hydrocarbon production. The drilling perforation technique maximizes the reservoir productivity index by minimizing damage. This can be best accomplished by attaining a better understanding of fluid flows that occur in the near-wellbore region during oil and gas operations. The present work aims to enhance oil recovery by modelling a two-phase flow through the near-wellbore region, thereby expanding industry knowledge about well performance. An experimental procedure was conducted to investigate the behavior of two-phase flow through a cylindrical perforation tunnel. Statistical analysis was coupled with numerical simulation to expand the investigation of fluid flow in the near-wellbore region that cannot be obtained experimentally. The statistical analysis investigated the effect of several parameters, including the liquid and gas flow rate, liquid viscosity, permeability, and porosity, on the injection build-up pressure and the time needed to reach a steady-state flow condition. Design-Expert® Design of Experiments (DoE) software was used to determine the numerical simulation runs using the ANOVA analysis with a Box-Behnken Design (BBD) model and ANSYS-FLUENT was used to analyses the numerical simulation of the porous media tunnel by applying the volume of fluid method (VOF). The experimental data were validated to the numerical results, and the comparison of results was in good agreement. The numerical and statistical analysis demonstrated each investigated parameter’s effect. The permeability, flow rate, and viscosity of the liquid significantly affect the injection pressure build-up profile, and porosity and gas flow rate substantially affect the time required to attain steady-state conditions. In addition, two correlations obtained from the statistical analysis can be used to predict the injection build-up pressure and the required time to reach steady state for different scenarios. This work will contribute to the clarification and understanding of the behavior of multiphase flow in the near-wellbore region.

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