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Averaged Dynamics of Fluids near the Oscillating Interface in a hele-shaw cell

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Fluid Dynamics & Materials Processing 2024年第4期20卷 847-857页

作者： Anastasia Bushueva Olga Vlasova Denis Polezhaev Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia

The steady flow in a hele-shaw cell filled with fluids with a high viscosity contrast in the presence of fluid oscillations is experimentally *** control of oscillatory dynamics of multiphase systems with interfaces is a challenging technological *** consider miscible(water and glycerol)and immiscible(water and high-viscosity silicone oil PMS-1000)fluids under subsonic oscillations perpendicular to the *** show that the interface shape depends on the amplitude and frequency of *** interface is undisturbed only in the absence of *** small amplitudes,the interface between water and glycerol widens due to *** the critical amplitude is reached,the interface becomes unstable to the fingering instability:Aqueous fingers penetrate the high-viscosity glycerol and induce intensive mixing of miscible fluids and associated decay of the *** the disappearance of the fingers,the interface takes a U-shape in the central part of the cell.A similar effect is observed for immiscible fluids:The oscillating interface tends to bend to the side of a high-viscosity ***,when the critical amplitude is reached,the fingering instability arises at the convex *** paper focuses on the causes of bending of the initially undisturbed interface between miscible or immiscible *** this purpose,we measure the steady flow velocity near the interface and in the bulk of a high-viscosity fluid using Particle Image Velocimetry(PIV).

关键词： hele-shaw cell oscillations steady flow miscible fluids immiscible fluids interface

Visualizing the dynamic progression of backward erosion piping in a hele-shaw cell

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 945-954页

作者： Gang ZHENG Jing-bo TONG Tian-qi ZHANG Zi-wu WANG Xun LI Ji-qing ZHANG Chun-yu QI Hai-zuo ZHOU Yu DIAO MOE Key Laboratory of Coast Civil Structure Safety Tianjin UniversityTianjin 300072China School of Science Tianjin UniversityTianjin 300072China China Railway Design Corporation Tianjin 300308China National Engineering Laboratory for Digital Construction and Evaluation Technology of Urban Rail Transit Tianjin 300308China

With the utilization of underground space,backward erosion piping(BEP)has been observed in many underground structures(e.g.,shield tunnels)founded on sandy ***,due to invisibility,the geometry of the eroded pipe and its spatial evolution with time during the piping process was still not *** this study,we developed a hele-shaw cell to visualize the dynamic progression of *** imaging process technology,we obtained a typical process of BEP(the erosion process can be divided into a piping progression phase and a piping stabilization phase),quantitatively characterized the formation of erosion pipes,and compared the patterns of erosion(e.g.,the erosion area A and the maximum erosion radius R)that spontaneously develop under different fluxes of *** most interesting finding is that the sand grains in a thicker hele-shaw model are easier to dislodge,which is possibly due to the granular system in a thicker model having more degrees of freedom,reducing the stability of the sand grains.

关键词： Backward erosion piping(BEP) Dynamic progression hele-shaw cell Visualize Imaging processing technology

On 2D approximations for dissolution problems in hele-shaw cells

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 104-120页

作者： Jianwei Guo Farid Laouafa Michel Quintard School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China National Institute for Industrial Environment and Risks(INERIS) Verneuil en Halatte 60550France Institut de Mecanique des Fluides de Toulouse(IMFT) Universite de ToulouseCNRSToulouse 31400France

In this paper, we study the dissolution problems occurring in laterally large 3D systems with very small dimensions along the third coordinate, such as fractures or hele-shaw cells. On the basis of the scale separation assumption, we apply upscaling to the 3D pore-scale model using the volume averaging method to develop 2D averaged equations. The influence of the choice of momentum equations on the accuracy of the 2D hele-shaw model is discussed, and we show that the results obtained using Darcy-Brinkman equations are better than those obtained using Darcy’s law, because of the consideration of the viscous boundary layer. The validity and accuracy of the resulting 2D model are assessed based on comparisons with full 3D solutions for problems corresponding to the existence of geometrical 3D features to which a simple averaging procedure along a line(i.e., the height of the gap) perpendicular to the 2D plane cannot be applied, such as the dissolution of pillars. The results show that when Péclet and Reynolds numbers exceed certain limits, 3D effects must be considered. Moreover, natural convection effects are important when the Rayleigh number is large.

关键词： dissolution hele-shaw cell upscaling natural convection

Isogeometric Analysis of a Phase Field Model for Darcy Flows with Discontinuous Data

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Chinese Annals of Mathematics,Series B 2018年第3期39卷 487-512页

作者： Luca DEDE Alfio QUARTERONI Modeling and Scientific Computing Mathematics Department"F.Brioschi"Politecnico di MilanoP.zza Leonardo da Vinci 3220133 MilanoItaly Modeling and Scientific Computing Math-section of MathematicsEcole Polytechnique Federale de LausanneCH-1015Switzerland(Honorary Professor)

The authors consider a phase field model for Darcy flows with discontinuous data in porous media;specifically,they adopt the hele-shaw-Cahn-Hillard equations of[Lee,Lowengrub,Goodman,Physics of Fluids,2002]to model flows in the hele-shaw cell through a phase field formulation which incorporates discontinuities of physical data,namely density and viscosity,across *** the spatial approximation of the problem,the authors use NURBS—based isogeometric analysis in the framework of the Galerkin method,a computational framework which is particularly advantageous for the solution of high order partial differential equations and phase field problems which exhibit sharp but smooth *** this paper,the authors verify through numerical tests the sharp interface limit of the phase field model which in fact leads to an internal discontinuity interface problem;finally,they show the efficiency of isogeometric analysis for the numerical approximation of the model by solving a benchmark problem,the so-called"rising bubble"problem.

关键词： Darcy flows Phase field hele-shaw cell Cahn-Hilliard equation Sharpinterface limit Isogeometric analysis

EXPERIMENTAL STUDY ON DARCY′S LAW IN hele-shaw cellS

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Transactions of Nanjing University of Aeronautics and Astronautics 2003年第2期20卷 134-139页

作者：孙建红许金造南京航空航天大学人机与环境工程系香港科技大学机械工程系

The basic physics of unsteady hele-shaw flow at high Reynolds numbers is mainly studied by an experimental measurement. In order to confirm the Darcy′s law in hele-shaw cell, since there is an analogy between flow in cells and that in porous media, progressive water waves are utilized to build an unsteady flow in a hele-shaw cell, and which complex wave number is measured by a wave height gauge. Meanwhile, theoretical analyses are used to compare with experimental data. Result shows Darcy′s Law is not exactly correct for unsteady hele-shaw flows, and it is expected to conduct a modified Darcy′s Law.

关键词： hele-shaw cell surface water wave Darcy′s law

Shared Memory Semi-Implicit Solver for Hydrodynamical Instability Processes

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Open Journal of Fluid Dynamics 2023年第1期13卷 32-46页

作者： Augusto Kielbowicz Diego Fernández Adriana Saal Claudio El Hasi Carlos Vigh Instituto de Ciencias Universidad Nacional de General Sarmiento Los Polvorines Argentina Departamento de Ciencias Básicas Facultad de Ingeniería Universidad Argentina de la Empresa Buenos Aires Argentina Departamento de Física Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Buenos Aires Argentina Instituto de Física Interdisciplinaria Aplicada (CONICET-UBA) Buenos Aires Argentina

The Advection-Diffusion Reaction (ADR) equation appears in many problems in nature. This constitutes a general model that is useful in various scenarios, from porous media to atmospheric processes. Particularly, it is used at the interface between two fluids where different types of instabilities due to surface mobility may appear. Together with the ADR equation, the Darcy-Brinkman model describes the phenomena known as fingering that appear in different contexts. The study of this type of system gains in complexity when the number of chemical species dissolved in both fluids increases. With more solutes, the increasing complexity of this phenomenon generally requires much computational power. To face the need for more computational resources, we build a solver tool based on an Alternating Direction Implicit (ADI) scheme that can be run in Central Processing Unit (CPU) and Graphic Processing Unit (GPU) architectures on any notebook. The implementation is done using the MATLAB platform to compare both versions. It is shown that using the GPU version strongly saves both resources and calculation times.

关键词： Fingering Fluids Simulations Numerical Solver hele-shaw cell

QUANTITATIVE ESTIMATES OF OIL LOSSES DURING MIGRATION,PARTⅡ:MEASUREMENT OF THE RESIDUAL OIL SATURATION IN MIGRATION PATHWAYS

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QUANTITATIVE ESTIMATES OF OIL LOSSES DURING MIGRATION,PARTⅡ...

中国科学院地质与地球物理研究所2008学术年会

作者： G.Vasseur SISYPHE UMRBoite 123Universite Paris 675252 Paris Cedex 05France.

Recent experimental observations have demonstrated that losses of oil in a secondary migration pathway depend largely on the characteristics of the pathway *** assessments of the residual saturation are required to quantify losses during *** the present paper,the authors report on experimental procedures designed to evaluate the oil saturation at various stages of the migrationlinvasion *** experiments made use of both apparatuses filled with an artificial medium composed of glass beads,and cores composed of reservoir sandstones from oilfields in NE *** saturation of residual oil in the pathways was measured by nuclear magnetic resonance imaging. Experiment results show that mobile oil continues to migrate in a porous medium when the supply of oil has been stopped,but that the migration pathway shrinks and may become disconnected into isolated *** active migration ceases,the residual oil saturation varies significantly from location to location within a pathway,and the average residual oil saturation falls to 30-60%, depending on grain size and composition.A porous medium composed of large grains commonly contains large pores and pore throats and thus may correlate with low residual oil saturations.

关键词： secondary migration NMRI oil saturation migration pathways hele-shaw cell oil losses.

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一种准二维柱面爆炸波加载装置的设计与验证

气体物理 2022年第2期7卷 40-48页

作者：刘澜薛琨史晓亮李建平北京理工大学机电学院北京100081

基于竖直爆轰管和径向hele-shaw cell,设计并搭建了一套准二维柱面爆炸波加载装置,可以实现对hele-shaw cell内部材料界面的径向冲击加载.竖直爆轰管内部的预混气体在底部点燃后,形成向上传播的冲击波,冲击波冲破爆轰管开口与hele-shaw ... 详细信息

基于竖直爆轰管和径向hele-shaw cell,设计并搭建了一套准二维柱面爆炸波加载装置,可以实现对hele-shaw cell内部材料界面的径向冲击加载.竖直爆轰管内部的预混气体在底部点燃后,形成向上传播的冲击波,冲击波冲破爆轰管开口与hele-shaw cell底板开孔之间的隔膜后,被hele-shaw cell的顶板阻碍,形成在hele-shaw cell内部径向传播的发散柱面波.通过同步的高速摄影和压力测试系统,可以获得hele-shaw cell内部燃爆产物气体的膨胀过程,同时将膨胀过程与hele-shaw cell内部冲击压力演化过程相耦合.实验发现hele-shaw cell内部的柱面冲击波具有良好的可重复性和环向压力均匀性.对燃爆过程和hele-shaw cell内部的柱面波传播过程进行了CFD数值模拟,当预混气体初始压力在100~250 kPa范围内时,可获得超压峰值在400~3000 kPa,冲量在50~180 Pa·s,Ma为2.8~4.4的柱面波,通过函数拟合得到了超压随径向传播距离呈幂函数衰减的规律,揭示了爆轰管内的燃爆过程对hele-shaw cell内部超压和冲量分布的影响.研究发现,通过调节燃爆过程和预混气初始条件可以实现对hele-shaw cell内部冲击波加载参数的调控.

关键词：冲击波加载准二维爆轰管 hele-shaw cell 波形可调