Enhanced electroosmotic flow of Herschel-Bulkley fluid in a channel patterned with periodically arranged slipping surfaces

被引:25
作者
Bhattacharyya, Somnath [1 ]
Bag, Naren [1 ]
机构
[1] Indian Inst Technol Kharagpur, Dept Math, Kharagpur 721302, W Bengal, India
关键词
WALL SLIP; YIELD-STRESS; VISCOELASTIC FLUIDS; CAPILLARY; INERTIA; GELS;
D O I
10.1063/1.5098508
中图分类号
O3 [力学];
学科分类号
08 ; 0801 ;
摘要
In this paper, we consider the electroosmotic flow (EOF) of a viscoplastic fluid within a slit nanochannel modulated by periodically arranged uncharged slipping surfaces and no-slip charged surfaces embedded on the channel walls. The objective of the present study is to achieve an enhanced EOF of a non-Newtonian yield stress fluid. The Herschel-Bulkley model is adopted to describe the transport of the non-Newtonian electrolyte, which is coupled with the ion transport equations governed by the Nernst-Planck equations and the Poisson equation for electric field. A pressure-correction-based control volume approach is adopted for the numerical computation of the governing nonlinear equations. We have derived an analytic solution for the power-law fluid when the periodic length is much higher than channel height with uncharged free-slip patches. An agreement of our numerical results under limiting conditions with this analytic model is encouraging. A significant EOF enhancement and current density in this modulated channel are achieved when the Debye length is in the order of the nanochannel height. Flow enhancement in the modulated channel is higher for the yield stress fluid compared with the power-law fluid. Unyielded region develops adjacent to the uncharged slipping patches, and this region expands as slip length is increased. The impact of the boundary slip is significant for the shear thinning fluid. The results indicate that the channel can be cation selective and nonselective based on the Debye layer thickness, flow behavior index, yield stress, and planform length of the slip stripes.
引用
收藏
页数:15
相关论文
共 62 条
[1]   Pressure-driven electrokinetic slip flows of viscoelastic fluids in hydrophobic microchannels [J].
Afonso, A. M. ;
Ferras, L. L. ;
Nobrega, J. M. ;
Alves, M. A. ;
Pinho, F. T. .
MICROFLUIDICS AND NANOFLUIDICS, 2014, 16 (06) :1131-1142
[2]  
[Anonymous], 1922, FLUIDITY PLASTICITY
[3]  
[Anonymous], 1991, Computational Techniques for Fluid Dynamics. Volume II: Specific Techniques fo r Different Flow Categories, DOI DOI 10.1007/978-3-642-58239-4_8
[4]   Electroosmotic flow of a non-Newtonian fluid in a microchannel with heterogeneous surface potential [J].
Bag, Naren ;
Bhattacharyya, S. .
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS, 2018, 259 :48-60
[5]   Anisotropic electro-osmotic flow over super-hydrophobic surfaces [J].
Bahga, Supreet S. ;
Vinogradova, Olga I. ;
Bazant, Martin Z. .
JOURNAL OF FLUID MECHANICS, 2010, 644 :245-255
[6]   Wall slip and flow of concentrated hard-sphere colloidal suspensions [J].
Ballesta, P. ;
Petekidis, G. ;
Isa, L. ;
Poon, W. C. K. ;
Besseling, R. .
JOURNAL OF RHEOLOGY, 2012, 56 (05) :1005-1037
[7]   The apparent hydrodynamic slip of polymer solutions and its implications in electrokinetics [J].
Berli, Claudio L. A. .
ELECTROPHORESIS, 2013, 34 (05) :622-630
[8]   Enhanced electroosmotic flow in a nano-channel patterned with curved hydrophobic strips [J].
Bhattacharyya, S. ;
Pal, S. K. .
APPLIED MATHEMATICAL MODELLING, 2018, 54 :567-579
[9]  
Bird R.B., 2007, TRANSPORT PHENOMENA
[10]   Induced-charge electro-osmosis of polymer-containing fluid around a metallic rod [J].
Canpolat, Cetin ;
Qian, Shizhi ;
Beskok, Ali .
MICROFLUIDICS AND NANOFLUIDICS, 2014, 16 (1-2) :247-255