LBM Simulation of Electro-Osmotic Flow (EOF) in Nano/Micro Scales Porous Media With an Inclusive Parameters Study

Volume 7: Fluids Engineering Systems and Technologies ◽

10.1115/imece2014-37831 ◽

2014 ◽

Author(s):

Ramin Zakeri ◽

Eon Soo Lee ◽

Mohammad Reza Salimi

Keyword(s):

Porous Media ◽

Zeta Potential ◽

Electric Field ◽

External Electric Field ◽

Complex Geometry ◽

Debye Length ◽

Ionic Concentration ◽

Numerical Code ◽

Channel Height ◽

Effective Parameters

In this paper, we present our results about simulation of 2D-EOF in Nano/Micro scales porous media using lattice Boltzmann method (LBM) in micro-channel for EOF. The high efficient numerical code use strongly high nonlinear Poisson Boltzmann equation to predicate behavior of EOF in complex geometry. The results are developed with precisely investigation of several effective parameters on permeability of EOF, such as geometry (channel height and number and location of charge), external electric field, thickness of Debye length (ionic concentration), and zeta potential. Our results are in excellent agreement with available analytical results. Our results show that for certain external electric field, zeta potential and porosity, there is an optimal Kh parameter (ionic concentration and channel height in this study) for velocity profiles. Based on the current study, homogenous zeta potential distribution on solid porous media, zeta potential and thickness of Debye length (Kh parameter) can dramatically affect on EOF permeability linearly or non-linearly, depend on amount of quantities. Thus, different arrangements are also considered. We show that prediction of EOF behavior in complex geometry with regarding role of effective parameters is completely possible for various applicable conditions.

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Simulation of Nano Polymer Chain Sensor in Electroosmotic Flow Using Dissipative Particle Dynamics (DPD) Method

Volume 7: Fluids Engineering Systems and Technologies ◽

10.1115/imece2014-37840 ◽

2014 ◽

Author(s):

Ramin Zakeri ◽

Eon Soo Lee

Keyword(s):

Zeta Potential ◽

Polymer Chain ◽

Electroosmotic Flow ◽

Dissipative Particle Dynamics ◽

Debye Length ◽

Flow Characteristics ◽

Channel Height ◽

Test Case ◽

Effective Parameters ◽

Linear Behavior

In this paper, we simulate the inflation of fixed two ends polymer chain curvature as nano sensor in EOF which it provides a porous media for DPD (dissipative particles dynamics) solvent particles and inflation is resulted. Particles are driven by electroosmotic flow in nanochannel which is as an external force in DPD algorithm and part of particles should move through a non-charged polymer chain which they affect on curvature of polymer chain. Our results for simple nanochannel in EOF are validated with analytical results and we have developed our results when a fixed two ends polymer chain subject in nanochannel as nano sensor in both cases including simple and stenosis nanochannel. Amount of inflation (displacement) of fixed two ends polymer chain is related to electroosmotic forces and interaction between particles. Our aim is that a relation between effective parameters in electroosmotic flow such as electric field, zeta potential, kh parameters and amount of inflation in polymer chain curvature (interaction between particles) is provided for each test case. Based on our results, there is a linear relation between some parameters such as external electrical field, zeta potential and kh parameters (effect of Debye length and channel height) in low electrosmotic forces but non-linear behavior is observed for high electroosmotic forces especially for stenosis channel case. This study opens some new way toward designing proper nano EOF sensors to measure flow characteristics in EOF applications.

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Modeling of Electroosmotic Nanoflows With Overlapped Double Layer

ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 2 ◽

10.1115/icnmm2011-58087 ◽

2011 ◽

Author(s):

Reza Nosrati ◽

Mehrdad Raisee ◽

Ahmad Nourbakhsh

Keyword(s):

Zeta Potential ◽

Double Layer ◽

Electric Double Layer ◽

Potential Distribution ◽

Present Model ◽

Ionic Concentration ◽

Channel Height ◽

Parabolic Profile ◽

Poisson Boltzmann ◽

Volume Method

In the present paper a new model is proposed for electric double layer (EDL) overlapped in nanochannels. The model aimed to obtain a deeper insight of transport phenomena in nanoscale. Two-dimensional Nernst and ionic conservation equations are used to obtain electroosmotic potential distribution in flow field. In the proposed study, transport equations for flow, ionic concentration and electroosmotic potential are solved numerically via finite volume method. Moreover, Debye-Hu¨ckle (DH) approximation and symmetry condition, which limit the application, are avoided. Thus, the present model is suitable for prediction of electroosmotic flows through nanochannels as well as complicated asymmetric geometries with large nonuniform zeta potential distribution. For homogeneous zeta potential distribution, it has been shown that by reduction of channel height to values comparable with EDL thickness, Poisson-Boltzmann model produces inaccurate results and must be avoided. Furthermore, for overlapped electric double layer in nanochannels with heterogeneous zeta potential distribution it has been found that the present model returns modified ionic concentration and electroosmotic potential distribution compare to previous EDL overlapped models due to 2D solution of ionic concentration distribution. Finally, velocity profiles in EDL overlapped nanochannels are investigated and it has been showed that for pure electroosmotic flow the velocity profile deviates from the expected plug-like profile towards a parabolic profile.

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3D Numerical Analysis of Velocity Profiles of PD, EO and Combined PD-EO Flows Through Microchannels

ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B ◽

10.1115/icnmm2006-96039 ◽

2006 ◽

Cited By ~ 1

Author(s):

Shahrzad Yazdi ◽

Reza Monazami ◽

Mahmoud A. Salehi

Keyword(s):

Electric Field ◽

External Electric Field ◽

Charge Distribution ◽

Three Dimensional ◽

Flow Patterns ◽

Ionic Concentration ◽

Micro Channel ◽

Micro Channels ◽

Wide Range ◽

Pressure Driven

In this paper, a three-dimensional numerical model is developed to analyze flow characteristics of pressure driven, electroosmotic and combined pressure driven-electroosmotic flows through micro-channels. The governing system of equations consists of the electric-field and flow-field equations. The solution procedure involves three steps. The net charge distribution on the cross section of the micro-channel is computed by solving two-dimensional Poisson-Boltzmann equation using the finite element method. Then, using the computed fluid’s charge distribution, the magnitude of the resulting body force due to interaction of an external electric field with the charged fluid is calculated along the micro-channel. Finally, three dimensional Navier-Stokes equations are solved by considering the presence of the electro-kinetic body forces in the flow system for electroosmotic and combined pressure driven electroosmotic flow cases. The results reveal that the flow patterns for combined PD-EO cases are significantly different from the parabolic velocity profile of the laminar pressure-driven flow. The effect of the liquid bulk ionic concentration and the external electric field strength on flow patterns through the square-shaped micro-channels is also investigated over a wide range of external electric field strengths and bulk ionic concentration.

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From electrodiffusion theory to the electrohydrodynamics of leaky dielectrics through the weak electrolyte limit

Journal of Fluid Mechanics ◽

10.1017/jfm.2018.567 ◽

2018 ◽

Vol 855 ◽

pp. 67-130 ◽

Cited By ~ 8

Author(s):

Yoichiro Mori ◽

Y.-N. Young

Keyword(s):

Electric Field ◽

Electric Fields ◽

Liquid Droplet ◽

Debye Length ◽

Ionic Concentration ◽

Liquid Interface ◽

Dielectric Fluids ◽

Debye Layer ◽

Tm Model ◽

Leaky Dielectric

The Taylor–Melcher (TM) model is the standard model for describing the dynamics of poorly conducting leaky dielectric fluids under an electric field. The TM model treats the fluids as ohmic conductors, without modelling the underlying ion dynamics. On the other hand, electrodiffusion models, which have been successful in describing electrokinetic phenomena, incorporate ionic concentration dynamics. Mathematical reconciliation of the electrodiffusion picture and the TM model has been a major issue for electrohydrodynamic theory. Here, we derive the TM model from an electrodiffusion model in which we explicitly model the electrochemistry of ion dissociation. We introduce salt dissociation reaction terms in the bulk electrodiffusion equations and take the limit in which the salt dissociation is weak; the assumption of weak dissociation corresponds to the fact that the TM model describes poor conductors. Together with the assumption that the Debye length is small, we derive the TM model with or without the surface charge convection term depending upon the scaling of relevant dimensionless parameters. An important quantity that emerges is the Galvani potential (GP), the jump in voltage across the liquid–liquid interface between the two leaky dielectric media; the GP arises as a natural consequence of the interfacial boundary conditions for the ionic concentrations, and is absent under certain parametric conditions. When the GP is absent, we recover the TM model. Our analysis also reveals the structure of the Debye layer at the liquid–liquid interface, which suggests how interfacial singularities may arise under strong imposed electric fields. In the presence of a non-zero GP, our model predicts that the liquid droplet will drift under an imposed electric field, the velocity of which is computed explicitly to leading order.

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Effective Excess Charge Density in Water Saturated Porous Media

VNU Journal of Science Mathematics - Physics ◽

10.25073/2588-1124/vnumap.4294 ◽

2018 ◽

Vol 34 (4) ◽

Author(s):

Luong Duy Thanh

Keyword(s):

Porous Media ◽

Zeta Potential ◽

Double Layer ◽

Electric Double Layer ◽

Electrical Potential ◽

Debye Length ◽

Excess Charge ◽

Geophysical Research ◽

Colloid Science ◽

Capillary Pore

A model for the effective excess charge in a capillary as well as in porous media is developed for arbitrary pore scales. The prediction of the model is then compared with another published model that is limited for a thin electric double layer (EDL) assumption. The comparison shows that there is a deviation between two models depending on the ratio of capillary/pore radius and the Debye length. The reasons for the deviation between two models are not only due to the thin EDL assumption to get electrical potential and charge distribution in pores but also to some other approximations for integral evaluations. The results suggest that the model developed in this work can be used with arbitrary capillary/pore scale and thus is not restricted to the thin EDL assumption. Keywords: Zeta potential, porous media, electric double layer, effective excess charge. References [1] M. Aubert, Q.Y. Atangana, Groundwater, 34 (1996) 1010–1016.[2] A. Finizola, J.-F. Lénat, O. Macedo, D. Ramos, J.-C. Thouret, F. Sortino, J. Volcanol. Geoth. Res., 135 (2004) 343–360.[3] C. Doussan, L. Jouniaux, J.-L. Thony, Journal of Hydrology 267 (2002) 173–185.[4] F. Perrier, M. Trique, B. Lorne, J.-P. Avouac, S. Hautot, P. Tarits, Geophys. Res. Lett. 25 (1998) 1955–1958.[5] Martinez-Pagan, P., A. Jardani, A. Revil, and A. Haas, Geophysics 75 (2010) WA17–WA25.[6] Naudet, V., A. Revil, J.-Y. Bottero, and P. Bgassat, Geophysical Research Letters 30 (2003).[7] V. Naudet, M. Lazzari, A. Perrone, A. Loperte, S. Piscitelli, V. Lapenna, Engineering Geology 98 (2008) 156-167.[8] A. Perrone, A. Iannuzzi, V. Lapenna, P. Lorenzo, S. Piscitelli, E. Rizzo, F. Sdao, Journal of Applied Geophysics 56 (2004) 17-29.[9] Jouniaux, L., A. Maineult, V. Naudet, M. Pessel, and P. Sailhac, C. R. Geoscience 341 (2009).[10] Revil, A., and A. Jardani, The Self-Potential Method: Theory and Applications in Environmental Geosciences, Cambridge University Press, 2013.[11] Hunter, R., Zeta Potential in Colloid Science: Principles and Applications, Colloid Science Series, Academic Press, 1981.[12] Leroy, P., and A. Revil, Journal of Colloid and Interface Science, 270 (2004) 371–380.[13] T. Ishido, H. Mizutani, Journal of Geophysical Research 86 (1981) 1763-1775.[14] P. W. J. Glover, E. Walker, M. Jackson, Geophysics 77 (2012) D17–D43.[15] Revil, A., and P. Leroy, Journal of Geophysical Research 109 (2004).[16] Linde, N., D. Jougnot, A. Revil, S. K. Matthäi, T. Arora, D. Renard, and C. Doussan, Geophys. Res. Lett. 34 (2007) L03306.[17] Revil A. and Mahardika H, Water Resources Research 49 (2013) 744–766.[18] Jardani, A., A. Revil, A. Bolève, A. Crespy, J. Dupont, W. Barrash and B. Malama, Geophysical Research Letters, 34 (2007) L24,403.[19] L. Guarracino, D. Jougnot, Journal of Geophysical Research - Solid Earth 123 (2018) 52-65.[20] Jackson M.D., Leinov E., International Journal of Geophysics 2012 (2012).[21] Gierst L., J. Am. Chem. Soc. 88 (1966) 4768.[22] Rice, C., and R. Whitehead, J. Phys. Chem. 69 (1965) 4017–4024.[23] Pride, S., Physical Review B 50 (1994) 15,678–15,696.[24] Bear, J., Dynamics of Fluids in Porous Media, Dover Publications, New York, 1988. [25] Chan I. Chung, Extrusion of Polymers: Theory & Practice, Hanser-2nd edition, 2010.[26] J. Vinogradov, M. Z. Jaafar, M. D. Jackson, Journal of Geophysical Research 115 (2010).

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