The coupled model of transient non-equilibrium interphase mass transfer rate of sliding bubble and two-phase flow in variable gradient drilling

Author(s):  
Ruiyao Zhang ◽  
Jun Li ◽  
Gonghui Liu ◽  
Hongwei Yang ◽  
Reyu Gao
2006 ◽  
Vol 49 (2) ◽  
pp. 271-278 ◽  
Author(s):  
Tomio OKAWA ◽  
Naoya SHIMADA ◽  
Akio KOTANI ◽  
Isao KATAOKA

Fluids ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 226
Author(s):  
Rashal Abed ◽  
Mohamed M. Hussein ◽  
Wael H. Ahmed ◽  
Sherif Abdou

Airlift pumps can be used in the aquaculture industry to provide aeration while concurrently moving water utilizing the dynamics of two-phase flow in the pump riser. The oxygen mass transfer that occurs from the injected compressed air to the water in the aquaculture systems can be experimentally investigated to determine the pump aeration capabilities. The objective of this study is to evaluate the effects of various airflow rates as well as the injection methods on the oxygen transfer rate within a dual injector airlift pump system. Experiments were conducted using an airlift pump connected to a vertical pump riser within a recirculating system. Both two-phase flow patterns and the void fraction measurements were used to evaluate the dissolved oxygen mass transfer mechanism through the airlift pump. A dissolved oxygen (DO) sensor was used to determine the DO levels within the airlift pumping system at different operating conditions required by the pump. Flow visualization imaging and particle image velocimetry (PIV) measurements were performed in order to better understand the effects of the two-phase flow patterns on the aeration performance. It was found that the radial injection method reached the saturation point faster at lower airflow rates, whereas the axial method performed better as the airflow rates were increased. The standard oxygen transfer rate (SOTR) and standard aeration efficiency (SAE) were calculated and were found to strongly depend on the injection method as well as the two-phase flow patterns in the pump riser.


1968 ◽  
Vol 31 (2) ◽  
pp. 273-303 ◽  
Author(s):  
Ronald Panton

Flow properties for the non-equilibrium two-phase flow of a gas-particle mixture are formulated from the theoretical standpoint. A quasi-one-dimensional flow containing an arbitrary volume of particles is considered, and mass transfer between the phases is allowed. It is shown that meaningful definitions of the flow properties of each phase can be constructed as area-averages of (time-averaged local flow-field properties). Special definitions of averages overcome the difficulties introduced by the fact that one phase does not occupy the entire region at all times. Conservation equations for the newly defined properties are given and criteria for their validity determined. The results give fresh interpretation to several aspects of two-phase flow: the particle-phase pressure is associated with the internal particle pressure, whereas Reynolds-stress terms are introduced by fluctuations in particle velocity. Reynolds stresses for both phases are important in laminar as well as turbulent flow and provide a significant particlephase viscous effect. The interphase momentum transfer because of condensation or vaporization is shown to be characterized by the particle-phase velocity irrespective of the direction of the mass transfer.


2021 ◽  
Vol 19 (3) ◽  
pp. 295-308
Author(s):  
Jin Zunlong ◽  
Liu Yonghao ◽  
Dong Rui ◽  
Wang Dingbiao ◽  
Chen Xiaotang

Abstract A numerical study of the gas–liquid two-phase flow and mass transfer in a square microchannel with a T-junction is carried out in this work. Through numerical simulation methods, the flow patterns of bubble flow, slug flow and annular flow are determined. By proposing a new flow pattern conversion relationship with different media and different speeds, 100 sets of CO2-water flow patterns and 100 sets of CO2-ethanol flow patterns are obtained. The effects of surface tension on flow pattern, bubble length and liquid plug length are studied. The pressure distribution and pressure drop are analyzed, and mass transfer is obtained through slug flow simulation, and the influencing factors of gas–liquid mass transfer are studied. The results show that the effect of surface tension on the length of the bubble and the length of the liquid plug is completely opposite, the pressure distribution is stepped, and the pressure drop increases with the increase of the gas–liquid velocity. In addition, it was found that the volumetric mass transfer coefficients of the bubble cap and the liquid film gradually decreased with time, and eventually stabilized. The increase in bubble velocity accelerates the mass transfer rate, while the increase in unit cell length slows the mass transfer rate. However, the influence of film thickness and liquid film length on mass transfer varies with time.


1969 ◽  
Vol 9 (03) ◽  
pp. 323-337 ◽  
Author(s):  
W.E. Culham ◽  
S.M. Farouq Ali ◽  
C.D. Stahl

Abstract One- and two-dimensional mathematical models have been developed that simulate transient, two-phase flow of hydrocarbon mixtures in porous media in a manner that accounts for interphase mass transfer. Numerical simulations of one-dimensional depletion-drive experiments using a two-component hydrocarbon fluid were used to establish the validity of the mathematical models. In addition, the experimental and numerical data were used to demonstrate that production rate had a relatively insignificant effect on the recovery of individual hydrocarbon components from the experimental system, and that attainment of equilibrium between phases is possible for a wide range of liquid and vapor velocities in reservoirs containing light hydrocarbon fluids. Results of some two-dimensional numerical simulations are also presented. Introduction This study was undertaken to develop a mathematical model that would simulate transient, two-phase flow of hydrocarbon mixtures in porous media under conditions that result in interphase mass transfer and to test the validity of the assumptions used to set up the model. In addition, the study was designed to determine if production rate influences the recovery of individual hydrocarbon components from reservoirs producing by depletion drive. Two-phase flow in porous media, with interchange of components between the two phases, is important in many petroleum recovery processes. Studies conducted within the last 3 years have outlined methods of solving multiphase flow problems incorporating mass transfer. Some of these studies have also indicated the importance of accounting for mass transfer under various producing conditions. An earlier works first demonstrated the importance of combining relative permeability data with equilibrium ratios in compositional balance methods. The mathematical model presented in this paper is formulated so that a phase behavior package, as described in previous papers, is not required as an integral part of the routine employed to solve for the primary dependent variables. The finite difference formulation is designed so that all these variables can be solved for simultaneously. This is accomplished by utilizing one basic set of equations. These innovations, which are in contrast to other models but are similar in some respects to the approach used by Taylor, render the total problem computationally simpler than any of the previously referenced formulations. The mathematical model was developed by combining Darcy's law with a continuity equation for each hydrocarbon component. The principal assumptions invoked in the formulation were that capillary forces and diffusional effects are negligible, and that thermodynamic equilibrium exists in the reservoir at all times. No assumption as to the type of vaporization process was made in formulating this model. Experimental data were required to complete this study. These were generated by conducting several depletion drive experiments. The experimental apparatus consisted of a sandstone core enclosed in a pressurized casing. The apparatus was designed in such a manner that the core could be charged with a liquid hydrocarbon mixture and depleted at different production rates. The experimental tests were designed to determine the effect of production rate on component recovery. SPEJ P. 323


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