This paper investigates two-dimensional, time-independent elecroosmotic pressure-driven flow generated by a direct current electric potential with asymmetrical and symmetrical zeta potential distributions along the microchannel walls. Fluid flow through the horizontal microchannel is simulated using a numerical method. Two different cases are proposed to study the effect of electric potential on the flow field. First, negative electric potential is applied on the microchannel walls. In this case, large segments with negative electric potential are initially placed on the first half of the microchannel walls with two different arrangements. Afterward, smaller segments with negative electric potential are placed on the microchannel walls. Next, negative electric potential is replaced by positive electric potential on the microchannel walls in the similar manner. It is shown that applying positive potential on the walls contributes to the localized circular flows within the microchannel. The size of these vortices is also proved to considerably vary with the applied zeta potential magnitude. Finally, the effect of wall zeta potential on heat transfer was studied for all the four types of microchannels by imposing a constant uniform heat flux on the walls. The Nusselt number plots indicate how heat transfer varies along the microchannel walls. The Nusselt number fluctuation can be observed where the positive and negative electric potentials are located.

References

References
1.
Mishchuk
,
N. A.
,
Heldal
,
T.
,
Volden
,
T.
,
Auerswald
,
J.
, and
Knapp
,
H.
,
2009
, “
Micropump Based on Electroosmosis of the Second Kind
,”
Electrophoresis
,
30
(
20
), pp.
3499
3506
.
2.
Chen
,
C.-H.
,
2009
, “
Thermal Transport Characteristics of Mixed Pressure and Electro-Osmotically Driven Flow in Micro- and Nanochannels With Joule Heating
,”
ASME J. Heat Transfer
,
131
(
2
), p.
022401
.
3.
Chen
,
L.
,
Ma
,
J.
, and
Guan
,
Y.
,
2004
, “
Study of an Electroosmotic Pump for Liquid Delivery and Its Application in Capillary Column Liquid Chromatography
,”
J. Chromatogr. A
,
1028
(
2
), pp.
219
226
.
4.
Takamura
,
Y.
,
Onoda
,
H.
,
Inokuchi
,
H.
,
Adachi
,
S.
,
Oki
,
A.
, and
Horiike
,
Y.
,
2003
, “
Low-Voltage Electroosmosis Pump for Stand-Alone Microfluidics Devices
,”
Electrophoresis
,
24
(
1–2
), pp.
185
192
.
5.
Wang
,
X.
,
Cheng
,
C.
,
Wang
,
S.
, and
Liu
,
S.
,
2009
, “
Electroosmotic Pumps and Their Applications in Microfluidic Systems
,”
Microfluid. Nanofluid.
,
6
(
2
), pp.
145
162
.
6.
Gitlin
,
I.
,
Stroock
,
A. D.
,
Whitesides
,
G. M.
, and
Ajdari
,
A.
,
2003
, “
Pumping Based on Transverse Electrokinetic Effects
,”
Appl. Phys. Lett.
,
83
(
7
), pp.
1486
1488
.
7.
Jahanshahi
,
A.
,
Axisa
,
F.
, and
Vanfleteren
,
J.
,
2012
, “
Fabrication of a Biocompatible Flexible Electroosmosis Micropump
,”
Microfluid. Nanofluid.
,
12
(
5
), pp.
771
777
.
8.
Gu
,
C.
,
Jia
,
Z.
,
Zhu
,
Z.
,
He
,
C.
,
Wang
,
W.
,
Morgan
,
A.
,
Lu
,
J. J.
, and
Liu
,
S.
,
2012
, “
Miniaturized Electroosmotic Pump Capable of Generating Pressures of More Than 1200 Bar
,”
Anal. Chem.
,
84
(
21
), pp.
9609
9614
.
9.
Wang
,
P.
,
Chen
,
Z.
, and
Chang
,
H.-C.
,
2006
, “
A New Electro-Osmotic Pump Based on Silica Monoliths
,”
Sens. Actuators, B
,
113
(
1
), pp.
500
509
.
10.
Horiuchi
,
K.
, and
Dutta
,
P.
,
2006
, “
Heat Transfer Characteristics of Mixed Electroosmotic and Pressure Driven Micro-Flows
,”
JSME Int. J. Ser. B Fluids Therm. Eng.
,
49
(
3
), pp.
812
819
.
11.
Horiuchi
,
K.
,
Dutta
,
P.
, and
Hossain
,
A.
,
2006
, “
Joule-Heating Effects in Mixed Electroosmotic and Pressure-Driven Microflows Under Constant Wall Heat Flux
,”
J. Eng. Math.
,
54
(
2
), pp.
159
180
.
12.
Chein
,
R.
,
Yang
,
Y. C.
, and
Lin
,
Y.
,
2006
, “
Estimation of Joule Heating Effect on Temperature and Pressure Distribution in Electrokinetic‐Driven Microchannel Flows
,”
Electrophoresis
,
27
(
3
), pp.
640
649
.
13.
Chen
,
C.-H.
,
2012
, “
Fully-Developed Thermal Transport in Combined Electroosmotic and Pressure Driven Flow of Power-Law Fluids in Microchannels
,”
Int. J. Heat Mass Transfer
,
55
(
7
), pp.
2173
2183
.
14.
Dutta
,
P.
,
Horiuchi
,
K.
, and
Yin
,
H.-M.
,
2006
, “
Thermal Characteristics of Mixed Electroosmotic and Pressure-Driven Microflows
,”
Comput. Math. Appl.
,
52
(
5
), pp.
651
670
.
15.
Iverson
,
B.
,
Maynes
,
D.
, and
Webb
,
B.
,
2004
, “
Thermally Developing Electroosmotic Convection in Rectangular Microchannels With Vanishing Debye-Layer Thickness
,”
J. Thermophys. Heat Transfer
,
18
(
4
), pp.
486
493
.
16.
Sphaier
,
L.
,
2012
, “
Integral Transform Solution for Heat Transfer in Parallel-Plates Micro-Channels: Combined Electroosmotic and Pressure Driven Flows With Isothermal Walls
,”
Int. Commun. Heat Mass Transfer
,
39
(
6
), pp.
769
775
.
17.
Sharma
,
A.
, and
Chakraborty
,
S.
,
2008
, “
Semi-Analytical Solution of the Extended Graetz Problem for Combined Electroosmotically and Pressure-Driven Microchannel Flows With Step-Change in Wall Temperature
,”
Int. J. Heat Mass Transfer
,
51
(
19
), pp.
4875
4885
.
18.
Erickson
,
D.
, and
Li
,
D.
,
2003
, “
Analysis of Alternating Current Electroosmotic Flows in a Rectangular Microchannel
,”
Langmuir
,
19
(
13
), pp.
5421
5430
.
19.
Zade
,
A. Q.
,
Manzari
,
M. T.
, and
Hannani
,
S. K.
,
2007
, “
An Analytical Solution for Thermally Fully Developed Combined Pressure–Electroosmotically Driven Flow in Microchannels
,”
Int. J. Heat Mass Transfer
,
50
(
5
), pp.
1087
1096
.
20.
Herr
,
A.
,
Molho
,
J.
,
Santiago
,
J.
,
Mungal
,
M.
,
Kenny
,
T.
, and
Garguilo
,
M.
,
2000
, “
Electroosmotic Capillary Flow With Nonuniform Zeta Potential
,”
Anal. Chem.
,
72
(
5
), pp.
1053
1057
.
21.
Kim
,
M.
,
Beskok
,
A.
, and
Kihm
,
K.
,
2002
, “
Electro-Osmosis-Driven Micro-Channel Flows: A Comparative Study of Microscopic Particle Image Velocimetry Measurements and Numerical Simulations
,”
Exp. Fluids
,
33
(
1
), pp.
170
180
.
22.
Dutta
,
P.
,
Beskok
,
A.
, and
Warburton
,
T. C.
,
2002
, “
Numerical Simulation of Mixed Electroosmotic/Pressure Driven Microflows
,”
Numer. Heat Transfer: Part A
,
41
(
2
), pp.
131
148
.
23.
Tang
,
G.
,
Yang
,
C.
,
Chai
,
C.
, and
Gong
,
H.
,
2004
, “
Numerical Analysis of the Thermal Effect on Electroosmotic Flow and Electrokinetic Mass Transport in Microchannels
,”
Anal. Chim. Acta
,
507
(
1
), pp.
27
37
.
24.
Zu
,
Y.
, and
Yan
,
Y.
,
2006
, “
Numerical Simulation of Electroosmotic Flow Near Earthworm Surface
,”
J. Bionic Eng.
,
3
(
4
), pp.
179
186
.
25.
Yan
,
D.
,
Yang
,
C.
, and
Huang
,
X.
,
2007
, “
Effect of Finite Reservoir Size on Electroosmotic Flow in Microchannels
,”
Microfluid. Nanofluid.
,
3
(
3
), pp.
333
340
.
26.
Mondal
,
M.
,
Misra
,
R. P.
, and
De
,
S.
,
2014
, “
Combined Electroosmotic and Pressure Driven Flow in a Microchannel at High Zeta Potential and Overlapping Electrical Double Layer
,”
Int. J. Therm. Sci.
,
86
, pp.
48
59
.
27.
Cho
,
C.-C.
, and
Chen
,
C.-L.
,
2012
, “
Characteristics of Combined Electroosmotic Flow and Pressure-Driven Flow in Microchannels With Complex-Wavy Surfaces
,”
Int. J. Therm. Sci.
,
61
, pp.
94
105
.
28.
Vocale
,
P.
,
Geri
,
M.
,
Morini
,
G.
, and
Spiga
,
M.
,
2014
, “
Electro-Osmotic Flows Inside Triangular Microchannels
,”
J. Physics: Conf. Ser.
, p.
012026
.
29.
Babaie
,
A.
,
Saidi
,
M. H.
, and
Sadeghi
,
A.
,
2012
, “
Heat Transfer Characteristics of Mixed Electroosmotic and Pressure Driven Flow of Power-Law Fluids in a Slit Microchannel
,”
Int. J. Therm. Sci.
,
53
, pp.
71
79
.
30.
Bianchi
,
F.
,
Ferrigno
,
R.
, and
Girault
,
H.
,
2000
, “
Finite Element Simulation of an Electroosmotic-Driven Flow Division at a T-Junction of Microscale Dimensions
,”
Anal. Chem.
,
72
(
9
), pp.
1987
1993
.
31.
Ebrahimi
,
S.
,
Hasanzadeh-Barforoushi
,
A.
,
Nejat
,
A.
, and
Kowsary
,
F.
,
2014
, “
Numerical Study of Mixing and Heat Transfer in Mixed Electroosmotic/Pressure Driven Flow Through T-Shaped Microchannels
,”
Int. J. Heat Mass Transfer
,
75
, pp.
565
580
.
32.
Ren
,
C. L.
, and
Li
,
D.
,
2005
, “
Improved Understanding of the Effect of Electrical Double Layer on Pressure-Driven Flow in Microchannels
,”
Anal. Chim. Acta
,
531
(
1
), pp.
15
23
.
33.
Fu
,
L.-M.
,
Lin
,
J.-Y.
, and
Yang
,
R.-J.
,
2003
, “
Analysis of Electroosmotic Flow With Step Change in Zeta Potential
,”
J. Colloid Interface Sci.
,
258
(
2
), pp.
266
275
.
34.
Molho
,
J. I.
,
Herr
,
A. E.
,
Desphande
,
M.
,
Gilbert
,
J.
,
Garguilo
,
M. G.
,
Paul
,
P. H.
,
John
,
P.
,
Woudenberg
,
T.
, and
Connel
,
C.
,
1998
, “
Fluid Transport Mechanisms in Microfluidic Devices
,” ASME Micro-Electro-Mechanical-Systems (
MEMS
), Vol.
66
, pp.
69
76
.
35.
Zhao
,
T.
, and
Liao
,
Q.
,
2002
, “
Thermal Effects on Electro-Osmotic Pumping of Liquids in Microchannels
,”
J. Micromech. Microeng.
,
12
(
6
), p.
962
.
36.
Mondal
,
S.
, and
De
,
S.
,
2013
, “
Mass Transport in a Porous Microchannel for Non‐Newtonian Fluid With Electrokinetic Effects
,”
Electrophoresis
,
34
(
5
), pp.
668
673
.
37.
Misra
,
J.
, and
Chandra
,
S.
,
2013
, “
Electro-Osmotic Flow of a Second-Grade Fluid in a Porous Microchannel Subject to an AC Electric Field
,”
J. Hydrodyn., Ser. B
,
25
(
2
), pp.
309
316
.
38.
Patankar
,
N. A.
, and
Hu
,
H. H.
,
1998
, “
Numerical Simulation of Electroosmotic Flow
,”
Anal. Chem.
,
70
(
9
), pp.
1870
1881
.
39.
Tang
,
G.
,
Yang
,
C.
,
Chai
,
C.
, and
Gong
,
H.
,
2003
, “
Modeling of Electroosmotic Flow and Capillary Electrophoresis With the Joule Heating Effect: the Nernst-Planck Equation Versus the Boltzmann Distribution
,”
Langmuir
,
19
(
26
), pp.
10975
10984
.
40.
Hu
,
Y.
,
Werner
,
C.
, and
Li
,
D.
,
2003
, “
Electrokinetic Transport Through Rough Microchannels
,”
Anal. Chem.
,
75
(
21
), pp.
5747
5758
.
41.
Tang
,
G.
,
Yan
,
D.
,
Yang
,
C.
,
Gong
,
H.
,
Chai
,
J. C.
, and
Lam
,
Y. C.
,
2006
, “
Assessment of Joule Heating and Its Effects on Electroosmotic Flow and Electrophoretic Transport of Solutes in Microfluidic Channels
,”
Electrophoresis
,
27
(
3
), pp.
628
639
.
42.
Arnold
,
A.
,
Nithiarasu
,
P.
, and
Tucker
,
P.
,
2008
, “
Finite Element Modelling of Electro-Osmotic Flows on Unstructured Meshes
,”
Int. J. Numer. Methods Heat Fluid Flow
,
18
(
1
), pp.
67
82
.
43.
Arnold
,
A.
,
Nithiarasu
,
P.
, and
Eng
,
P.
,
2008
, “
Electro-Osmotic Flow in Microchannels
,”
Proc. Inst. Mech. Eng., Part C
,
222
(
5
), pp.
753
759
.
44.
Yang
,
R.-J.
,
Fu
,
L.-M.
, and
Hwang
,
C.-C.
,
2001
, “
Electroosmotic Entry Flow in a Microchannel
,”
J. Colloid Interface Sci.
,
244
(
1
), pp.
173
179
.
45.
Yang
,
R.-J.
,
Fu
,
L.-M.
, and
Lin
,
Y.-C.
,
2001
, “
Electroosmotic Flow in Microchannels
,”
J. Colloid Interface Sci.
,
239
(
1
), pp.
98
105
.
46.
Probstein
,
R. F.
,
2005
,
Physicochemical Hydrodynamics: An Introduction
,
Wiley
,
New York
.
47.
Senturia
,
S. D.
,
2007
,
Microsystem Design
,
Springer Science & Business Media
, New York.
48.
Karniadakis
,
G.
,
Beskok
,
A.
, and
Aluru
,
N.
,
2006
,
Microflows and Nanoflows: Fundamentals and Simulation
,
Springer Science & Business Media
,
New York
.
49.
Wang
,
W.
, and
Soper
,
S. A.
,
2006
,
Bio-MEMS: Technologies and Applications
,
CRC Press
,
Boca Raton, FL
.
50.
Tabeling
,
P.
,
2010
,
Introduction to Microfluidics
,
Oxford University Press
,
New York
.
51.
Hiemenz
,
P. C.
, and
Rajagopalan
,
R.
,
1997
,
Principles of Colloid and Surface Chemistry, Revised and Expanded
,
CRC Press
,
Boca Raton, FL
.
52.
Henry
,
D.
,
1931
, “
The Cataphoresis of Suspended Particles. Part I. The Equation of Cataphoresis
,”
Proc. Royal Soc. London A
,
133
(
821
), pp.
106
129
.
53.
Kim
,
H.
,
Kwak
,
H.
, and
Westerweel
,
J.
,
2011
, “
Assessment of Mixing Problem on the EOF With Thermal Effects
,”
Colloids Surf., A
,
376
(
1
), pp.
53
58
.
54.
Tang
,
G.
,
Yang
,
C.
,
Chai
,
J.
, and
Gong
,
H.
,
2004
, “
Joule Heating Effect on Electroosmotic Flow and Mass Species Transport in a Microcapillary
,”
Int. J. Heat Mass Transfer
,
47
(
2
), pp.
215
227
.
55.
Chorin
,
A. J.
,
1997
, “
A Numerical Method for Solving Incompressible Viscous Flow Problems
,”
J. Comput. Phys.
,
135
(
2
), pp.
118
125
.
56.
Tamamidis
,
P.
,
Zhang
,
G.
, and
Assanis
,
D. N.
,
1996
, “
Comparison of Pressure-Based and Artificial Compressibility Methods for Solving 3D Steady Incompressible Viscous Flows
,”
J. Comput. Phys.
,
124
(
1
), pp.
1
13
.
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