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RESEARCH ARTICLE
Hydromagnetic Convection Flow in a Porous Medium BoundedBetween Vertical Wavy Wall and Parallel Flat Wall: AnalysisUsing Darcy–Brinkman–Forchheimer Model
R. R. Singh • Ajay Kumar Singh • Usha Singh •
Atul Kumar Singh • N. P. Singh
Received: 24 April 2013 / Revised: 18 March 2014 / Accepted: 21 March 2014 / Published online: 25 June 2014
� The National Academy of Sciences, India 2014
Abstract The present paper deals with two-dimensional
convection flow and heat transfer of a viscous, incom-
pressible, conducting fluid, through porous medium con-
fined in a vertical wavy wall and parallel flat wall under the
influence of transverse magnetic field. The non-linear
equations governing the flow are solved by linearization
technique under the assumption that the flow consists of
two parts; a mean part and a perturbed part. Darcy–
Brinkman–Forchheimer model is used to visualize the
problem. Exact solutions are obtained for the mean part
and the perturbed part is solved using long wave approxi-
mation method. The effects of various parameters, zeroth
order and total axial velocity fields, transverse velocity,
temperature distribution, shear stress and heat transfer rate
are presented graphically and discussed.
Keywords Hydromagnetic convection flow �Porous medium � Vertical wavy walls
List of Symbols
a Amplitude,
B0 Uniform magnetic field in y0-direction,
C Prescribed constant,
Cp Specific heat at constant pressure,
Da Darcy number,
F Forchheimer parameter,
g Gravitational acceleration,
Gr Buoyancy parameter,
H Distance of flat wall,
k Thermal conductivity,
K0
Permeability of the medium,
K Permeability parameter,
KT Thermal conductivity,
L Characteristic length,
M Magnetic parameter,
Nu Nusselt number,
p0
Dimensional pressure,
p Non-dimensional pressure,
Pr Prandtl number,
T0
Temperature of the fluid in the boundary layer,
T Non-dimensional temperature,
Tf
0Temperature at the surface of the flat wall,
Tw
0Temperature at the surface of wavy wall,
Tm
0Temperature of the ambient fluid,
TR Temperature ratio parameter,
u0, v0
Velocity components in x0
and y0-direction,
u, v Velocity components in x and y -direction,
x0, y0
Dimensional cartesian coordinate,
x, y Non-dimensional cartesian coordinate
Greek Symbols
e Non-dimensional amplitude,
2 Porosity of the porous medium,
b Volumetric coefficient of thermal expansion,
k0
Dimensional wave number,
k Non-dimensional wave number,
R. R. Singh (&) � A. K. Singh � U. Singh
Department of Mathematics, C. L. Jain College, Firozabad 283
203, India
e-mail: [email protected]
A. K. Singh
e-mail: [email protected]
A. K. Singh
Department of Mathematics, V. S. S. D. College, Kanpur 208
002, India
N. P. Singh
Department of Mathematics, Rama Institute of Engineering &
Technology, Mandhana, Kanpur 209 217, India
e-mail: [email protected]
123
Proc. Natl. Acad. Sci., India, Sect. A Phys. Sci. (July–September 2014) 84(3):409–431
DOI 10.1007/s40010-014-0153-5
c Viscosity ratio parameter,
q Density of the fluid,
r Electrical conductivity of the fluid,
leff Effective viscosity of the fluid,
l Viscosity of the fluid,
t Kinematic viscosity,
sw Skin-friction at the wavy wall (y = -1),
sf Skin-friction at the flat wall (y = 1)
Introduction
The study of heat transfer from irregular surfaces is of
importance, because irregular surfaces are often present in
engineering applications. Therefore, the study of convec-
tive flows in wavy channels is essential to observe the flow
characteristics and heat transfer processes in several heat
devices with variations in material parameters. The channel
consisting of a corrugated wall and flat wall is one of the
several devices employed for enhancing the heat transfer
efficiency of industrial processes. Surface non-uniformities
of such channels are encountered in insulating systems and
grain storage containers. The presence of roughness on the
surface disturbs the flow past surfaces and alerts the heat
transfer rate. As such, the natural convection in vertical
channels consisting of a wavy surface and a flat surface is a
model problem for the investigation of momentum and heat
transfer from roughened and flat surfaces of the wall in
order to understand effect of material parameters on flow
characteristics.
Lekoudis et al. [1] investigated incompressible boundary
layer flow of Newtonian viscous fluid over a wavy wall
analytically and observed that at low Reynolds numbers the
waviness of the wall quickly ceases as the liquid is dragged
along the wall, whereas at large Reynolds numbers the
effects of viscosity are confined to a thin layer close to the
wall. Bordner [2] presented non-linear analysis of laminar
boundary layer flow over a periodic wavy surface and
concluded that some non-linear terms in the disturbed
boundary layer equations are of first order, if the wave
amplitude and disturbance sub-layer are comparable in
magnitude. Vajravelu and Sastri [3] considered free con-
vection heat transfer in a viscous incompressible fluid
confined between a vertical wavy wall and a flat wall to
study the effects of wavy geometry, buoyancy and material
parameters. Das and Ahmed [4] extended this study con-
sidering free convection flow of a viscous incompressible
fluid between a long vertical wavy wall and parallel flat
wall under the influence of uniform transverse magnetic
field. Caponi et al. [5] obtained analytical solution of
laminar flow of an incompressible viscous fluid over a
moving wavy surface and observed significant effects of
the phase of the wavy surface on the flow field and
temperature distribution in natural convection through
porous media. Yao [6] investigated natural convection flow
of Newtonian fluids using finite-difference scheme to study
the heat transfer from isothermal vertical wavy surface.
Rao et al. [7] investigated hydromagnetic convective flow
in a vertical wavy channel with heat source/sink and dis-
cussed the effects of magnetic field, internal heat genera-
tion/absorption and amplitude wavelength ratio on the heat
transfer coefficient. Rees and Pop [8, 9] studied free con-
vection flow along a vertical wavy surface with constant
wall temperature and uniform wall flux respectively.
Hossain and Pop [10] investigated the magnetohydrody-
namic boundary layer flow as well as heat transfer from a
continuously moving wavy surface and observed that
waviness of the surface suppresses the momentum transfer
but increases the heat transfer, Alim et al. [11] studied heat
transfer from a fixed wavy vertical surface in the presence
of transverse magnetic field and discussed the effects of
waviness on flow behaviour and heat transfer rate. Reddy
et al. [12] presented theoretical analysis on convection flow
of a viscous heat generating fluid in a vertical wavy
channel considering unsteadiness due to the imposed
oscillatory flux on the flow using perturbation technique to
solve the non-linear equations governing the flow. Patidar
and Purohit [13] investigated free convection flow of a
viscous incompressible fluid in porous medium between
two long vertical wavy walls and found that the heat
transfer varies periodically along the wavy surface.
Taneja and Jain [14] examined unsteady free convection
flow of viscous fluid in the presence of temperature
dependent heat source/sink in a rotating wavy channel with
travelling thermal waves and solved the non-linear equa-
tions governing the flow using perturbation technique.
Hossain et al. [15] considered natural convection flow
along a heated vertical wavy surface in presence of tem-
perature dependent viscosity and found that the tempera-
ture dependent viscosity has significant effect on the flow
behaviour and heat transfer at the wavy surface. Molla
et al. [16] studied natural convection flow along a vertical
wavy surface and observed the effect of internal heat
generation/absorption. In their analysis, the equations
governing the flow are mapped into the domain of flat
vertical plate and then solved numerically employing the
implicit finite-difference method and Keller-box scheme.
Sarangi and Jose [17] studied unsteady flow of a viscous,
electrically conducting fluid through a porous medium
confined between two long non-conducting wavy walls
under the influence of uniform magnetic field. Tak and
Kumar [18] investigated two-dimensional hydromagnetic
free convection flow of a viscous fluid in a vertical wavy
channel with heat source considering one channel wall as
isothermal and the other as adiabatic. Yao [19] investigated
the same problem for the natural convection flow along a
410 R. R. Singh et al.
123
vertical wavy surface with complex boundary conditions.
Molla and Hossain [20] have investigated the effect of
thermal radiation on steady two-dimensional mixed con-
vection flow along a vertical wavy surface using the
appropriate similarity variables. For the analysis, the basic
equations governing the flow are transformed into conve-
nient form, and then solved numerically employing two
efficient methods, namely; Keller-box method (KBM) and
straight forward finite difference method (SFFDM).
The references pertaining to flow through porous media
are based on Darcy law. However its importance and
ramifications in process design and operation have been
recognized only during the last three/four decades. As an
improvement, Irmay [21] presented an analysis on the
theoretical derivation of Darcy and Forchheimer models
and observed that Forchheimer model is more appropriate
at low Darcy numbers. Nakayama et al. [22] studied free
convection over a non-isothermal body of arbitrary shape
in a saturated porous medium using Forchheimer equation.
Consequently, the mechanism of convective heat transfer
in a porous medium has occurred in the literature for many
processes and unit operations involving a range of geo-
metric configurations such as the Darcy-Forchheimer
model and Darcy Brinkman-Forchheimer model.
Kladias and Prasad [23] experimentally verified the
Darcy–Brinkman–Forchheimer model for natural convec-
tion in porous media. Shenoy [24] studied natural, forced
and mixed convective heat transfer in non-Newtonian
power law fluid-saturated porous medium using Darcy-
Forchheimer model. Vafai and Kim [25] presented
numerical study based on the Darcy–Brinkman–Forchhei-
mer model for the forced convection in a composite system
containing fluid and porous regions and discussed about the
limitations of the Darcy–Brinkman–Forchheimer equa-
tions. Sequentially, Knupp and Lage [26] studied general-
ized form of Forchheimer-extended Darcy flow model to
the permeability case via a variation principle. Marpu [27]
investigated the Forchheimer and Brinkman extended
Darcy flow model for natural convection in a vertical
cylindrical porous medium. Whitaker [28] presented the-
oretical derivation of the Forchheimer flow model using
modern statistical averaging technique. Nakayama [29]
considered unified treatment of Darcy-Forchheimer
boundary layer flows. Besides, Bennethum and Giorgi [30],
Giorgi [31], Lees and Yang [32], Levy et al. [33], Chen
et al. [34] and Vafai [35] have studied Darcy-Forchheimer
model for different flow situations. The papers of Srinivas
and Muthuraj [36] and Tasnim et al. [37] are also on the
same line.
Paul et al. [38] have analysed the transient behaviour of
natural convection flow in porous region bounded by two
vertical walls as a result of asymmetric heating/cooling of
the channel walls using Forchheimer-Brinkman extended
Darcy model. More recently, Singh et al. [39] extended the
work of Paul et al. [38] considering the presence of internal
heat generation/absorption under the influence of uniform
transverse magnetic field within the limitations described
by Nield and Bejan [40]. In order to simulate momentum
transfer within the porous medium, Brinkman-Forchheimer
extended Darcy model is used and convection currents
between the walls occur as a result of change in the tem-
perature of the channel walls to that of the temperature of
the flow domain. Common method of producing convec-
tive flow is used, wherein the thermal energy is supplied
externally to create temperature difference across the sys-
tem. However, heat transfer in fluid flow by natural con-
vection as a result of difference in temperature gradient of
two vertical walls is also affected by temperature ratio of
the channel walls which is of immense importance partic-
ularly in heat transfer devices in industrial processes and
aerospace technology. Therefore, the present study
addresses the free convective flow of viscous incompress-
ible fluid through porous medium confined in vertical
channel consisting of a wavy wall and a parallel flat wall. A
generalized porous media model, namely, Brinkman-
Forchheimer extended Darcy model is considered in order
to simulate momentum transfer in porous medium. Since
new emerging technological models are applicable over a
wide range of porosity, the present paper deals with flow
through porous medium using Brinkman-Forchheimer
extended Darcy model in the presence of transversely
applied uniform magnetic field. Besides, the convection
phenomenon between the walls is set by changing the
temperature of the walls to that of the fluid temperature and
a non-dimensional parameter (buoyancy force parameter)
is used to characterize the temperature of vertical walls
with respect to the fluid temperature. The present model
enhances the applicability of the models suggested by Paul
et al. [38] and Singh et al. [41]. The model can have
possible application in heat transfer devices of industrial
processes, nuclear energy technology and geothermal
systems.
Formulation of the Problem
We consider steady two-dimensional laminar free con-
vection flow of an incompressible, electrically conducting,
viscous fluid through a homogeneous porous medium
confined in an open ended vertical channel consisting of a
wavy wall and a flat wall as shown in Fig. 1. A uniform
magnetic field is applied perpendicular to the walls, i.e.
normal to the flow region. It is assumed that the magnetic
Reynolds number is small, so that the induced magnetic
field is neglected in comparison to the applied magnetic
field (Ferraro and Plumpton [42]).
Hydromagnetic Convection Flow in a Porous Medium 411
123
The wavy and flat walls are respectively maintained at
different constant temperatures Tw
0and Tf
0such that the fluid
temperature Tm
0= Tw
0. Besides, the present analysis is
based on the following assumptions:
(i) All the fluid properties are constant except influence
of density variation with temperature in buoyancy
term in the momentum equation.
(ii) The density is a linear function of temperature so that
usual Boussinesq approximation is taken into account.
(iii) The wavelength k0
of the wavy wall is large
compared with width of the channel.
(iv) In the energy equation, the dissipative effect is
negligible.
(v) The inter-particle and inertia-particle heat transfer
effects are negligible.
(vi) Darcy-Brinkman-Forchhiemer model is considered
to simulate momentum transfer in porous media,
which is applicable over a wide range of porosity
(Nield and Bejan [40]).
(vii) Transport properties of the fluid are constant and the
fluid rises in the channel driven by buoyancy forces.
(viii) Both the walls are in stationary position, as such the
boundary conditions on velocity components u0and
v0
are the no slip conditions.
Under the above stated configuration and assumptions,
the equations governing the flows are:
Continuity equation:
ou0
ox0þ ov0
oy0¼ 0: ð1Þ
Momentum equations:
u0ou0
ox0þ v0
ou0
oy0¼ � 1
qop0
ox0þ
leff
qo2u0
ox02þ o2u0
oy02
� �
þ gb T 0 � T0
m
� �� t
ku0 � rB2
0
qu0 � Fffiffiffi
kp u
02: ð2Þ
u0ov0
ox0þ v0
ov0
oy0¼ � 1
qop0
oy0þ
leff
qo2v0
ox02þ o2v0
oy02
� �� t
kv0
� Fffiffiffikp v
02: ð3Þ
Energy equation:
u0oT 0
ox0þ v0
oT 0
oy0¼ KT
qCp
o2T 0
ox02þ o2T 0
oy02
� �: ð4Þ
The relevant boundary conditions on velocity and
temperature are:
u0 ¼ 0; v
0 ¼ 0; T0 ¼ T
0
w at y0 ¼ �H þ a cos k
0x0
� �;
u0 ¼ 0; v
0 ¼ 0; T0 ¼ T
0
f at y0 ¼ H:
9=;ð5Þ
We introduce following non-dimensional variables and
parameters:
x ¼ x0
H; y ¼ y0
H; u ¼ Hu0
t; v ¼ Hv0
t; c ¼
leff
l;
p ¼ H2qp0
l2; T ¼ T 0 � T 0m
T 0w � T 0m; ; k ¼ k0H and, e ¼ a
H; Da
¼ k
H2:
M ¼ffiffiffiffiffirqt
rB0H magnetic parameterð Þ;Gr
¼gbH3 T 0w � T 0m
� �t2
buoyancy parameterð Þ;
Pr ¼ lCp
KT
Prandtl numberð Þ:
The symbols are defined in the nomenclature.
Introducing above mentioned non-dimensional variables
and parameters, Eqs. (1)–(4) becomes:
ou
oxþ ov
oy¼ 0: ð6Þ
uou
oxþ v
ou
oy¼ � op
oxþ c
o2u
ox2þ o2u
oy2
� �
þ GrT � 1
Dau�M2u� Fffiffiffiffiffiffi
Dap u2:
ð7Þ
Fig. 1 Physical model and coordinate system
412 R. R. Singh et al.
123
uov
oxþ v
ov
oy¼�op
oyþ c
o2v
ox2þ o2v
oy2
� �� 1
Dav� Fffiffiffiffiffiffi
Dap v2: ð8Þ
Pr uoT
oxþ v
oT
oy
� �¼ o2T
ox2þ o2T
oy2: ð9Þ
The boundary conditions (5) on velocity and
temperature in non-dimensional form are:
u ¼ 0; v0 ¼ 0; T ¼ 1; y ¼ �1þ e cos kx;
u ¼ 0; v0 ¼ 0; T ¼ TR; y ¼ 1:
)ð10Þ
where TR ¼T 0
f�T 0m
T 0w�T 0m(temperature ratio parameter).
Now we proceed for the solution of Eqs. (6)–(9) under
boundary conditions (10).
Solution of the Problem
In order to obtain the solution of Eqs. (7)–(9) satisfying the
boundary conditions (10), we assume that the solution con-
sists of a mean part and a perturbed part so that the velocity,
temperature and pressure distribution can be expressed as:
u x; yð Þ ¼ u0 yð Þ þ eu1 x; yð Þ;v x; yð Þ ¼ ev1 x; yð Þ;
T x; yð Þ ¼ T0 yð Þ þ eT1 x; yð Þ;p x; yð Þ ¼ p0 yð Þ þ ep1 x; yð Þ;
9>>>=>>>;: ð11Þ
where e is the amplitude, used as perturbation parameter.
The perturbed quantities u1, v1, T1 and p1 are small com-
pared to mean quantities.
Introducing Eq. (11) in Eqs. (6)–(9) and boundary
conditions (10), we obtain:
Zeroth order equations and boundary conditions:
d2T0
dy2¼ 0: ð12Þ
cd2u0
dy2� 1
DaþM2
� �u0 þ GrT0 þ C � Fffiffiffiffiffiffi
Dap u2
0 ¼ 0:
ð13Þ
where � op0
ox¼ C.
u00 ¼ 0; u01 ¼ 0 at y ¼ �1;
u00 ¼ 0; u01 ¼ 0 at y ¼ 1:
)ð14Þ
First order equations and boundary conditions:
ou1
oxþ ov1
oy¼ 0: ð15Þ
u0
ou1
oxþ v1
ou0
oy¼ � op1
oxþ c
o2u1
ox2þ o2u1
oy2
� �þ GrT1
� 1
DaþM2
� �u1 �
2FffiffiffiffiffiffiDap u0u1: ð16Þ
u0
ov1
ox¼ � op1
oyþ c
o2v1
ox2þ o2v1
oy2
� �� 1
Dav1: ð17Þ
Pr u0
oT1
oxþ v1
oT0
oy
� �¼ o2T1
ox2þ o2T1
oy2: ð18Þ
u1 ¼� coskxdu0
dy;v1 ¼ 0;T1 ¼� coskx
dT0
dyat y¼�1;
u1 ¼ 0;v1 ¼ 0;T1 ¼ 0 at y¼ 1:
9=;ð19Þ
In arriving at the boundary conditions at the wavy wall
y = -1, the actual boundary conditions are transformed to
mean position. This is justified when e � 1, i.e., when the
amplitude (e) of the disturbance is small compared with the
disturbance of the wavelength (Lekoudis et al. [1]; Tuck
and Kouzoubov [43]).
The solution of Eq. (12) under the boundary conditions
(14) is:
T0 yð Þ ¼ TR � 1ð Þ2
yþ TR þ 1
2: ð20Þ
To solve Eq. (13), we assume:
u0 yð Þ ¼ u00 yð Þ þ Fu01 yð Þ: ð21Þ
Introducing (21) into Eq. (13), we obtain:
d2u00
dy2� A1u00 ¼ �A2y� A3: ð22Þ
d2u01
dy2� A1u01 ¼
1
cffiffiffiffiffiffiDap u2
00; ð23Þ
where A1 ¼ 1c
1DaþM2
� �; A2 ¼ Gr TR�1ð Þ
2c ; A3 ¼ Gr TRþ1ð Þþ2C
2cThe boundary conditions (14), become:
u00 ¼ 0; u01 ¼ 0 at y ¼ �1;
u00 ¼ 0; u01 ¼ 0 at y ¼ 1:
)ð24Þ
The solutions of Eqs. (22) and (23) satisfying boundary
conditions (24) are:
u00 yð Þ ¼ C1effiffiffiffiA1
py þ C2e�
ffiffiffiffiA1
py þ A2
A1
yþ A3
A1
: ð25Þ
u01 yð Þ ¼ C3effiffiffiffiA1
py þ C4e�
ffiffiffiffiA1
py þ K3e2
ffiffiffiffiA1
py þ K4e�2
ffiffiffiffiA1
py
þK5yeffiffiffiffiA1
py þ K6ye�
ffiffiffiffiA1
py þ K7 y2 � yffiffiffiffiffi
A1
p� �
effiffiffiffiA1
py
þK8 y2 þ yffiffiffiffiffiA1
p� �
e�ffiffiffiffiA1
py þ K9 y2 þ 2
A1
� �þ K10yþ K11:
ð26Þ
In order to solve the first order Eqs. (16)–(18), we
introduce the stream function w(x, y) such that:
u1 ¼ �owoy; v1 ¼
owox: ð27Þ
Hydromagnetic Convection Flow in a Porous Medium 413
123
Introducing Eq. (27) into Eqs. (16)–(18), in view of the
continuity Eq. (15), the governing equations for the
perturbed flow and heat transfer after eliminating p1 are
as follows:
u0
o3wox3þ o3w
oxoy2
� �� o2u0
oy2
owox� c 2
o4wox2oy2
þ o4wox4þ o4w
oy4
� �
þ 1
DaþM2
� �o2woy2þ Gr
oT1
oyþ 1
Da
o2wox2
þ 2FffiffiffiffiffiffiDap u0
o2woy2þ ou0
oy
owoy
� �¼ 0: ð28Þ
Pr u0
oT1
oxþ ow
ox
oT0
oy
� �¼ o2T1
ox2þ o2T1
oy2: ð29Þ
In view of boundary conditions (19), we assume general
solution for w and T1 in the following form:
w x; yð Þ ¼ RealX1r¼0
wrkreikx
!¼ Real w0eikx þ w1keikx
:
ð30Þ
T1
x; yð Þ ¼ RealX1r¼0
hrkreikx
!¼ Real h0eikx þ h1keikx
ð31Þ
Introducing Eqs. (30) and (31) into Eqs. (28) and (29),
we get the following set of ordinary differential equations
for (r = 0, 1):
d2h0
dy2¼ 0: ð32Þ
cd4w0
dy4� 1
DaþM2
� �d2w0
dy2¼ Gr
dh0
dy
þ 2FffiffiffiffiffiffiDap u0
d2w0
dy2þ du0
dy
dw0
dy
� �: ð33Þ
cd4w1
dy4� 1
DaþM2
� �d2w1
dy2
¼ Grdh1
dyþ i u0
d2w0
dy2� w0
d2u0
dy2
� �
þ 2FffiffiffiffiffiffiDap u0
d2w1
dy2þ du0
dy
dw1
dy
� �:
ð34Þ
d2h1
dy2¼ iPr u0h0 þ w0
dT0
dy
� �: ð35Þ
In the light of Eqs. (30), (31) and (27), the boundary
conditions (19) corresponding to w0, h0, w1 and h1 become:
w0 ¼ 0;dw0
dy¼ du0
dy; h0 ¼ �
dT0
dyat y ¼ �1;
w0 ¼ 0;dw0
dy¼ 0; h0 ¼ 1 at y ¼ 1:
9>>=>>;
ð36:1Þ
w1 ¼ 0;dw1
dy¼ 0;h1 ¼ 0 at y¼�1;
w1 ¼ 0;dw1
dy¼ 0;h1 ¼ 0 at y¼ 1; h1ð Þy¼�1¼ 0;
dh1
dy
� �y¼1
¼ 0; w1ð Þy¼�1¼ 0;dw1
dy
� �y¼�1
¼ 0:
9>>>>>>>=>>>>>>>;ð36:2Þ
The solution of Eq. (32) satisfying corresponding
boundary condition (36.1) is:
h0 ¼ C5yþ C6: ð37Þ
Equations (33) and (34) are coupled equations and can
not be solved directly. Hence we assume:
w0 ¼ w00 þ Fw01 and w1 ¼ w10 þ Fw11: ð38Þ
Introducing Eq. (38) into Eqs. (33) and (34) we obtain:
d4w00
dy4� A1
d2w00
dy2¼ C5
cGr: ð39Þ
d4w01
dy4�A1
d2w01
dy2¼ 2
cffiffiffiffiffiffiDap u00
d2w00
dy2þ du00
dy
dw00
dy
� �: ð40Þ
d4w10
dy4� A1
d2w10
dy2¼ Gr
cdh1
dyþ i
cu00
d2w00
dy2� w00
d2u00
dy2
� �
ð41Þ
d4w11
dy4� A1
d2w11
dy2¼ i
cu00
d2w01
dy2þ u01
d2w00
dy2� w01
d2u00
dy2
�
�w00
d2u01
dy2
�þ 2
cffiffiffiffiffiffiDap u00
d2w10
dy2þ du00
dy
dw10
dy
� �:
ð42Þ
The boundary conditions corresponding to w00, w01, w10
and w11 are:
w00 ¼ 0;w01 ¼ 0;dw00
dy¼ du00
dy;dw01
dy¼ du01
dyat y ¼ �1;
w10 ¼ 0;w11 ¼ 0;dw10
dy¼ 0;
dw11
dy¼ 0; at y ¼ �1;
w00 ¼ 0;w01 ¼ 0;dw00
dy¼ 0;
dw01
dy¼ 0 at y ¼ 1;
w10 ¼ 0;w11 ¼ 0;dw10
dy¼ 0;
dw11
dy¼ 0; at y ¼ 1:
9>>>>>>>>>>>=>>>>>>>>>>>;
ð43Þ
The solutions of Eqs. (39)–(42) satisfying (43) under
corresponding boundary conditions (36.1):
w00 yð Þ ¼ C7yþ C8 þ C9effiffiffiffiA1
py þ C10e�
ffiffiffiffiA1
py � K14y2:
ð44Þ
w01 yð Þ ¼ C11yþ C12 þ C13effiffiffiffiA1
py þ C14e�
ffiffiffiffiA1
py þ K16e2
ffiffiffiffiA1
py
þ K17e�2ffiffiffiffiA1
py þ K18ye
ffiffiffiffiA1
py � K19ye�
ffiffiffiffiA1
py
þ K20y2effiffiffiffiA1
py � K21y2e�
ffiffiffiffiA1
py � K22y3 þ K23y2: ð45Þ
414 R. R. Singh et al.
123
The solution of Eq. (35) introducing Eqs. (21) and (38)
satisfying conditions (43) is:
h1 ¼ C15yþ C16 þ iPr K31yþ K32ð Þe2ffiffiffiffiA1
py
h
þ K33yþ K34ð Þe�2ffiffiffiffiA1
py
þ K35y3 þ K36y3 þ K37yþ K38
� �effiffiffiffiA1
py
þ K39y3 þ K40y3 þ K41yþ K42
� �e�
ffiffiffiffiA1
py
þK43y5 þ K44y4 þ K45y3 þ K46y2�: ð46Þ
w10 ¼ C17yþ C18 þ C19effiffiffiffiA1
py þ C20e�
ffiffiffiffiA1
py
þ i K51yþ K52ð Þe2ffiffiffiffiA1
py
nþ K53yþ K54ð Þe�2
ffiffiffiffiA1
py
þ K55y4 þ K56y3 þ K57y2 þ K58y� �
effiffiffiffiA1
py
þ K59y4 þ K60y3 þ K61y2 þ K62y� �
e�ffiffiffiffiA1
py
þ K63y6 þ K64y5 þ K65y4 � K66y3 � K67y2g: ð47Þ
w11 ¼ C21yþ C22 þ C23effiffiffiffiA1
py þ C24e�
ffiffiffiffiA1
py
þ i K78e3ffiffiffiffiA1
py þ K79e�3
ffiffiffiffiA1
py
nþ K80e2
ffiffiffiffiA1
py
þ K81e�2ffiffiffiffiA1
py þ K82ye3
ffiffiffiffiA1
py þ K83ye�3
ffiffiffiffiA1
py
þ K84ye2ffiffiffiffiA1
py þ K85ye�2
ffiffiffiffiA1
py þ K86ye
ffiffiffiffiA1
py
þ K87ye�ffiffiffiffiA1
py þ K88y2e2
ffiffiffiffiA1
py þ K89y2e�2
ffiffiffiffiA1
py
þ K90y2effiffiffiffiA1
py þ K91y2e�
ffiffiffiffiA1
py þ K92y3e2
ffiffiffiffiA1
py
þ K93y3e�2ffiffiffiffiA1
py þ K94y3e
ffiffiffiffiA1
py þ K95y3e�
ffiffiffiffiA1
py
þ K96y4e2ffiffiffiffiA1
py þ K97y4e�2
ffiffiffiffiA1
py þ K98y4e
ffiffiffiffiA1
py
þ K99y4e�ffiffiffiffiA1
py þ K100y5e
ffiffiffiffiA1
py þ K101y5e�
ffiffiffiffiA1
py
þ K102y6effiffiffiffiA1
py þ K103y6e�
ffiffiffiffiA1
py � K104y7 � K105y6
� K106y5 þ K107y4þK108y3 þ K109y2�:
ð48Þ
Based on these solutions, the first order quantities w1
and h1 can be expressed in the following form:
w1 ¼ wr þ iwið Þ ¼ w10 þ kw11: ð49Þh1 ¼ hr þ ihið Þ ¼ h10 þ kh11; ð50Þ
where the suffix r denotes the real part and i denotes the
imaginary part.
Considering only the real part, the expressions for first
order velocity and first order temperature become:
u1 ¼ edwi
dxksin kxð Þ � dwr
dycos kxð Þ
� �: ð51Þ
v1 ¼ e �kwrsin kxð Þ � k2wicos kxð Þ� �
: ð52Þ
T1 ¼ e hrcos kxð Þ � ksin kxð Þhið Þ: ð53Þ
The entire solution for the velocity components and
temperature distribution is the summation of the mean part
and the perturbed part.
Shear Stress
The shearing stress (sxy) at any point in the fluid in non-
dimensional form is given by:
sxy ¼ou
oyþ ov
ox¼ du0
dyþ eeikx du1
oyþ eikeikxv1 yð Þ: ð54Þ
Therefore, the shear stress (sw) at the wavy wall y =
-1 ? e cos (kx) and the shear stress (sf) at the parallel flat
wall y = 1 in non-dimensional form can be expressed as:
sw ¼du0
dy
� �y¼�1
þeRe eikx d2u0
dy2�1ð Þ þ d2w1
dy2
� �� : ð55Þ
and
sf ¼du0
dy
� �y¼1
þeRe eikx d2wdy2
1ð Þ� �
: ð56Þ
Heat Transfer Rate
The heat transfer rate in terms of Nusselt number (Nu) in
non-dimensional form is given by:
Nu ¼ oT
oy¼ dT0
dyþ eRe eikx dT1
dy
� �: ð57Þ
Hence, the Nusselt number (Nuw) at the wavy wall and
the Nusselt number (Nuf) at the flat wall in non-
dimensional form take the form:
Nuw ¼dh0
dy
� �y¼�1
þeRe eikx dhdy�1ð Þ
� �: ð58Þ
Nuf ¼dh0
dy
� �y¼1
þeRe eikx dhdy
1ð Þ� �
: ð59Þ
Results and Discussion
Consideration of the Darcy–Brinkman–Forchheimer model
gives rise to an additional empirical parameter (F), which
is known as Forchheimer parameter (inertia constant). The
numerical value of the Forchheimer parameter (F) depends
upon the porosity of the porous medium (2). If the porous
medium consists of concrete (ordinary mixes) or concrete
(bituminous) then2 lies in the range 0.02 B 2 B 0.07
(Neild and Bejan, [40]). When 2 = 0.02, the value of F is
found as 0.01 approximately. As such F � 1, which is
used as perturbation parameter. The solutions for axial
velocity (u), transverse velocity (v) and temperature dis-
tribution (T) are numerically evaluated for several sets of
values of parameters. The solutions for the velocity fields
and temperature distribution show that the flow is governed
by the Darcy number (Da), Grashof number (Gr),
Hydromagnetic Convection Flow in a Porous Medium 415
123
kinematic viscosity ratio (c), magnetic parameter (M),
Forchheimer parameter (F), Prandtl number (Pr) and wall
temperature ratio parameter (TR). In order to analyse the
effect of different parameters on the behaviour of transport
phenomenon, several sets of the values of parameters are
used for all the graphs except the varying one. Also, the
shear stress at the wavy wall, sw; shear stress at the flat
wall, sf; the Nusselt number at the wavy wall, Nuw and the
Nusselt number at the flat wall, Nuf, are calculated
numerically and presented graphically. Equations (2) and
(3) show that we distinguish between the fluid viscosity (l)
and the effective viscosity (leff) used in the Brinkman term
following computer simulation study of Martys et al. [44]
and experimental investigation by Gilver and Altobelli
[45]. These studies demonstrate that there are situations,
particularly in aerospace technology, when it becomes
important to distinguish between these two coefficients.
The experimental study of Gilver and Altobelli [45], dis-
closes the fact that the ratio of effective viscosity (leff) to
the fluid velocity (l) lies in the range 5.1 \ leff/lf \ 10.9.
The Forchheimer parameter (inertia constant) F, appearing
in Eq. (1) is evaluated from the following empirical for-
mula suggested by Ergun [46].
F ¼ 1:75ffiffiffiffiffiffiffiffiffiffiffiffiffiffi150 23p
The temperature ratio parameter (TR) is important due to
its fundamental effects on transport processes between the
vertical wavy wall and the parallel flat wall. This parameter
essentially fixes the orientation of the ambient fluid
temperature (Tm
0) with respect to the temperature (Tw
0) of
the vertical wavy wall and the temperature (Tf
0) of the parallel
flat wall with the consideration T0
w [ T0
m. The case TR \ 0
implies T0f \T
0m, whereas the case TR [ 0 implies T
0f [ T
0m.
The case TR = 0 is a symmetric wall heating case, i.e. the
flat wall temperature (Tf
0) is equal to the temperature of the
ambient fluid (Tm
0). The case TR = 1 implies that the wavy
wall and flat wall are maintained at equal temperature,
whereas TR = -1 implies that the average of the
temperatures of the wavy wall (Tw
0) and the flat wall (Tf
0) is
equal to the fluid temperature (Tm
0). In the analysis, the
amplitude parameter (e) and kx are fixed as 0.02 and 0.78
respectively for all the computations. For practical
applications in nuclear technology and geothermal
systems, one important case; namely, the cooling (Gr [ 0)
of the wavy and flat wall is considered. The values of Prandtl
number (Pr) are chosen to be 0.71, 1.0 and 7.0, which
correspond to air, electrolyte solutions and water
respectively at 20 �C and one atmosphere pressure. These
are important fluids generally used in energy and aerospace
technologies (Rosa, [47]; Blums, [48]). The numerical
values of the remaining parameters are chosen either
arbitrarily or following Malashetty et al. [49]. The effects
of material parameters on the axial velocity (u), zeroth order
velocity (u0), transverse velocity (v), temperature
distribution (T), shear-stress at the wavy wall (sw); shear
stress at the flat wall (sf); rate of heat transfer (Nusselt
number) at the wavy wall (Nuw) and the parallel flat wall
(Nuf) are presented graphically and discussed.
Figure 2a illustrates the effect of Grashof number (Gr)
and the magnetic parameter (M) on the zeroth order axial
velocity (u0).The effect of Grashof number (Gr) and the
magnetic parameter (M) on the total axial velocity (u) is
shown in Fig. 2b. Physically, an increase in the numerical
value of Grashof number (Gr) implies an increase in the
buoyancy force, which supports the zeroth order axial
velocity (u0) as well as the total axial velocity (u). As such,
an increase in Grashof number (Gr) increases the flow.
Also, TR = 0.5 indicates that the temperature of the flat
wall (Tf
0) is less than the temperature of the wavy wall,
which implies an enhanced velocity in the vicinity of the
wavy wall. The physics behind the decrease in the zeroth
order axial velocity and the total axial velocity due to
increase in the magnetic field lies in the fact that the pre-
sence of the transversely applied magnetic field produces a
retarding force (Lorentz force) similar to the drag force,
which reduces the axial velocities u0 and u. Mathemati-
cally, the hydromagnetic drag embodied in the term -
M2u in the Eq. (7) retards the zeroth order axial velocity as
well as the total axial velocity. Due to this property of the
magnetic field, it is used as an important controlling device
in nuclear energy systems heat transfer, where momentum
development can be reduced by enhancing the magnetic
field.
(a) (b)
Fig. 2 Effect of Grashof number (Gr) and magnetic field (M) on
a zeroth order axial velocity (u0) and b total axial velocity (u) at
Da = 10-5, k = 0.05, F = 0.01, Pr = 1.0, [ = 0.02, c = 6.0,
TR = 0.5 and kx = 0.78
416 R. R. Singh et al.
123
Figure 3a illustrates the effect of the temperature ratio
parameter (TR) and the magnetic field parameter (M) on the
zeroth order axial velocity (u0) for the case TR \ 0, in the
range -1 B TR \ 0. The effect of the temperature ratio
parameter (TR) and the magnetic field (M) on the axial
velocity (u) is shown in Fig. 3b. The physics behind this
phenomenon lies in the fact that TR \ 0 implies that the
temperature of the wavy wall (Tw
0) is greater than the
temperature of the flat wall (Tf
0) and less than the temper-
ature of the ambient fluid (Tm
0), i.e. the inequality
Tw
0[ Tm
0[ Tf
0holds. As such the fluid is gaining heat from
the wavy wall only so that enhanced velocity is noted in the
vicinity of the wavy wall. In particular, when TR = -1, the
average of the temperatures of the wavy wall and the flat
wall is equal to the fluid temperature Tm
0so that the velocity
up to half of the channel width from the wavy wall
decreases, which remains positive, whereas reverse flow is
noted in the remaining half of the channel width towards
the flat wall.
Figure 4a shows the influence of the temperature ratio
parameter (TR) and the magnetic parameter (M) on the
zeroth order axial velocity (u0) for the case TR C 0, in the
range 0 B TR B 1. The effect of the temperature ratio
parameter (TR) and the magnetic field (M) on the axial
velocity (u) is illustrated in Fig. 4b. Figures 3a, b and 4a, b
show that the effect of wall temperature ratio (TR) on the
zeroth order velocity (u0) and the total axial velocity (u) is
to increase both the velocities for the cases TR = 0 and
TR = 1, whereas for TR = -1, the velocity increases in
half of the channel width from the wavy wall and decreases
at the flat wall, i.e. flow reversal is noted at the right flat
wall. In addition, it is noted that the magnitude of velocity
is optimum for TR = 1 and minimum for TR = -1. When
TR = 0, the velocity profiles of the zeroth order velocity
and the total axial velocity are observed more enhanced in
the locality of the wavy wall in comparison with the flat
wall because the fluid is gaining heat from the wavy wall
only.
Figure 5a shows the effect of Darcy number (Da) and
the magnetic field (M) on the zeroth order axial velocity
(u0). The effect of Darcy number (Da) and the magnetic
field (M) on the total axial velocity (u) is shown in Fig. 5b.
Increase in the Darcy number (Da) physically implies less
solid particles in the porous matrix so that the resistance
opposing the flow decreases, i.e. the bulk porous medium
resistance is lowered as Darcy number increases. As such,
the momentum development in the flow region is increased,
which enhances the velocity.
Figure 6a illustrates the effect of viscosity ratio (c) and
the magnetic field (M) on the zeroth order velocity (u0).
The effect of viscosity ratio parameter (c) and the magnetic
parameter (M) on total axial velocity is represented in
Fig. 6b. Physically, increase in viscosity ratio implies,
decrease in the viscousness of the ambient fluid, so that the
resistance between the flow layers decreases, As such, the
zeroth order axial velocity as well as total axial velocity
increase.
Figure 7a represents the effect of Forchheimer param-
eter (F) and the magnetic field (M) on the zeroth order axial
velocity (u0). The effect of Forchheimer parameter (F) and
(a) (b)
Fig. 3 Effect of temperature ratio (TR \ 0) on a zeroth order axial
velocity (u0) and b total axial velocity (u) at Gr = 4.0, Da = 10-5,
k = 0.05, F = 0.01, Pr = 1.0,[ = 0.02, c = 6.0 and kx = 0.78
(a) (b)
Fig. 4 Effect of temperature ratio (TR C 0) on a zeroth order axial
velocity (u0) and b total axial velocity (u) at Gr = 4.0, Da = 10-5,
k = 0.05, F = 0.01, Pr = 1.0, [ = 0.02, c = 6.0 and kx = 0.78
Hydromagnetic Convection Flow in a Porous Medium 417
123
the magnetic parameter (M) on total axial velocity is rep-
resented in Fig. 7b. The reason behind this phenomena lies
in the fact that increase in Forchheimer parameter
(F) implies presence of less solid particles in the porous
matrix so that the resistance of bulk porous medium is
lowered, which increases momentum development of the
flow regime, thereby enhancing the axial velocity.
Figure 8a shows the effect of Prandtl number (Pr) and
the magnetic field (M) on the zeroth order velocity (u0).
The effects of Prandtl number (Pr) and the magnetic
parameter (M) on total axial velocity are shown in Fig. 8b.
Mathematically, Prandtl number (Pr) defines the ratio of
momentum diffusivity to thermal diffusivity, consequently
lower axial velocity is observed with increase in Prandtl
number. A distinct decrease in velocity with increase in M,
confirms the property of magnetism, which is used as an
important controlling mechanism in nuclear energy sys-
tems and heat transfer, where momentum development can
be reduced in axial flow regime by enhancing the magnetic
field.
Figure 9a represents profiles of the transverse velocity
(v) for different values of the Grashof number (Gr) and the
magnetic field (M). The effect of viscosity ratio parameter
(c) and magnetic field (M) on the transverse velocity (v) is
shown in Fig. 9b. The transverse velocity (v) is normal to
the axial velocity (u), as such the effects of the Grashof
number (Gr), the viscosity ratio parameter (c) and the
magnetic parameter (M) are reverse to that of axial flow.
Figure 10a shows the effect of Prandtl number (Pr) and
the magnetic field (M) on the transverse velocity (v). The
effect of temperature ratio parameter (TR) and the magnetic
field (M) on the transverse velocity (v) is shown in
Fig. 10b. It may be noted that water (Pr = 7.0) enhances
the transverse velocity (v) more effectively in the negative
direction in comparison with air (Pr = 0.71) and electro-
lyte solutions (Pr = 1.0).
Figure 11 shows the profiles of the temperature distri-
bution (T) the channel for different values of the temper-
ature ratio parameter (TR). The curve demonstrates that the
temperature remain constant throughout the channel and is
(a) (b)
Fig. 5 Effect of Darcy number (Da) on a zeroth order axial velocity
(u0) and b total axial velocity (u) at Gr = 4.0, TR = 0.5, k = 0.05,
F = 0.01, Pr = 1.0, [ = 0.02, c = 6.0 and kx = 0.78
(a) (b)
Fig. 6 Effect of viscosity ratio (c) on a zeroth order axial velocity
(u0) and b total axial velocity (u) at Gr = 4.0, TR = 0.5, k = 0.05,
F = 0.01, Pr = 1.0, [ = 0.02, Da = 10-5 and kx = 0.78
(a) (b)
Fig. 7 Effect of Forchheimer parameter (F) on a zeroth order axial
velocity (u0) and b total axial velocity (u) at Gr = 4.0, TR = 0.5,
k = 0.05, c = 6.0, Pr = 1.0, [ = 0.02, Da = 10-5 and kx = 0.78
418 R. R. Singh et al.
123
independent of the distance y, whereas the curve for
TR = -1, is a straight line which makes an angle of 45� to
the y-axis. This explains the fact that the temperature
diminishes uniformly with distance. Also, for the case
TR = 0, the curve is also a straight line.
(a) (b)
Fig. 8 Effect of Prandtl number (Pr) on the a zeroth order axial
velocity (u0) and b total axial velocity (u) at Gr = 4.0, TR = 0.5,
k = 0.05, c = 6.0, F = 0.01, [ = 0.02, Da = 10-5 and kx = 0.78
(a) (b)
Fig. 9 Profiles of transverse velocity (v) for different values of
a Grashof number (Gr) and magnetic field (M), b viscosity ratio (c)
and magnetic field (M) at TR = 0.5, k = 0.05, F = 0.01, Pr = 1.0,
[ = 0.02, Da = 10-5 and kx = 0.78
(a) (b)
Fig. 10 Profiles of transverse velocity (v) for different values of
a Prandtl number (Pr) and magnetic field (M), b temperature ratio
parameter (TR) and magnetic field (M) at Da = 10-5, k = 0.05,
F = 0.01, c = 6.0, [ = 0.02, Gr = 4.0 and kx = 0.78
Fig. 11 Profiles of temperature (T) for different values of the
temperature ratio parameter (TR) at Da = 10-5, k = 0.05, F = 0.01,
Pr = 1.0, M = 0.5, c = 6.0, [ = 0.02, Gr = 4.0 and kx = 0.78
Hydromagnetic Convection Flow in a Porous Medium 419
123
Figure 12 shows the profiles of temperature distribution
(T) versus y for different values of the Prandtl number (Pr).
Higher Pr value fluids transfer heat less effectively com-
pared with lower Pr value fluids. Consequently, lower tem-
perature is observed with increase in the Prandtl number.
Besides, two curves (M = 0 and M = 0.5) for each Pr value
expose the fact that the presence of magnetic field increases
the temperature due to Brownian moment.
Figure 13 shows shear stress (sw) at the wavy wall and
shear stress (sf) at the flat wall versus Grashof number (Gr)
for different values of the magnetic parameter (M). It is
noted that the shear stress (sw) at the wavy wall increases
with increase in Grashof number (Gr) and the magnetic
parameter (M) for the assigned values of the material
parameters.
Figure 14 shows the curve for Nusselt number (Nuw, Nuf)
versus Grashof number (Gr) for different values of the
magnetic parameter (M). It is observed that the effect of the
Grashof number (Gr) is to decrease the Nusselt number
(Nuw) at the wavy wall and to increase the Nusselt number
(Nuf) at the flat wall. Also, as the magnetic parameter
(M) increases, the Nusselt number at the wavy wall (Nuw) as
well as the Nusselt number at the flat wall (Nuf) decreases.
Fig. 12 Profiles of temperature (T) for different values of Prandtl
number (Pr) at Da = 10-5, k = 0.05, F = 0.01, TR = 0, M = 0.5,
c = 6.0, [ = 0.02, Gr = 4.0 and kx = 0.78
Fig. 13 Shear stress versus Grashof number (Gr) for different values
of magnetic field (M) at Da = 10-5, k = 0.05, F = 0.01, Pr = 1.0,
TR = 0.5, c = 6.0, [ = 0.02 and kx = 0.78
Fig. 14 Nusselt number versus Grashof number (Gr) for different
values of magnetic field (M) at Da = 10-5, k = 0.05 F = 0.01,
Pr = 1.0, TR = 0.5, c = 6.0, [ = 0.02 and kx = 0.78
420 R. R. Singh et al.
123
Figure 15 represents the graphs of the present study and
that of steady case of Paul et al. [38]. It is observed that the
graphs of the present study are in agreement under the
same physical situation and the boundary conditions.
However, the curves shown in the figure differ due to the
change of the physical situation of the channel and the
boundary conditions.
Conclusion
From the present study, the following conclusions may be
drawn:
(i) The effect of increasing Grashof number (Gr) is to
increase the zeroth order axial velocity (u0).
(ii) The effect of the magnetic parameter (M) is to
decrease the zeroth order axial velocity and total axial
velocity.
(iii) An increase in the numerical value of the temper-
ature ratio TR \ 0 in the range -1 B TR \ 0
decreases the zeroth order axial velocity (u0) and
the total axial velocity (u), whereas an increase in TR
increases these velocities and the reverse flow exists.
For the case TR [ 0 an increase in TR increases u0 as
well as u in the range 1 C TR C 0. When TR = 0, the
enhanced velocity is noted near the wavy wall and
when TR = 1, the velocity increases symmetrically.
(iv) The magnitude of velocity is optimum for TR = 1
and minimum TR = -1. When TR = -1, the reverse
flow is noted at the right flat wall.
(v) The effect Darcy number (Da) is to increase in the
zeroth order velocity (u0) as well as in total axial
velocity (u).
(vi) The zeroth order velocity (u0) and total axial velocity
(u) increase with increase in the viscosity ratio
parameter (c).
(vii) An increase in the Grashof number (Gr) decreases
the transverse velocity (v), whereas reverse effect is
noted for magnetic field.
(viii) An increase in the Prandtl number (Pr) or the
magnetic parameter (M) increases the magnitude of
the transverse velocity (v).
(ix) For TR = 1, the temperature field is constant and is
independent of the distance parallel to the y-axis;
whereas for TR = -1, the temperature decreases at
constant rate towards the y-axis.
(x) The temperature increases with increase in the
magnitude of Prandtl number.
(xi) The shear stress (sf) at the flat wall decreases whereas
the shear stress (sw) at the wavy wall increases as
Grashof number (Gr) increases.
(xii) The effect of Grashof number (Gr) is to decrease the
Nusselt number (Nuw) at the wavy wall and to
increase the Nusselt number (Nuf) at the flat wall.
Appendix
C1 ¼K2e�
ffiffiffiffiA1
p� K1e
ffiffiffiffiA1
p
e2ffiffiffiffiA1
p� e�2
ffiffiffiffiA1
p ; C2 ¼K1e�
ffiffiffiffiA1
p� K2e
ffiffiffiffiA1
p
e2ffiffiffiffiA1
p� e�2
ffiffiffiffiA1
p
C3 ¼K13e�
ffiffiffiffiA1
p� K12e
ffiffiffiffiA1
p
e2ffiffiffiffiA1
p� e�2
ffiffiffiffiA1
p ; C4 ¼K12e�
ffiffiffiffiA1
p� K13e
ffiffiffiffiA1
p
e2ffiffiffiffiA1
p� e�2
ffiffiffiffiA1
p ;
C5 ¼1þ TR
4; C6 ¼
3� TR
4;
C7 ¼1
a5
C10 � C9ð Þ; C8 ¼ �K14 � a1C9 � a2C10;
C9 ¼a5K15 a4 � a2ð Þ þ 4a7K14
a6 a4 � a2ð Þ þ a7 a3 � a1ð Þ
C10 ¼4a6K14 � a5 a3 � a1ð ÞK15
a6 a4 � a2ð Þ þ a7 a3 � a1ð Þ ; C11 ¼K26 � K24
2
� effiffiffiffiA1
p� e�
ffiffiffiffiA1
p
2
!C13 � C14ð Þ;
C12 ¼ K25 � K24 � a1C13 � a2C14; C13 ¼a9K30 � a4 � a2ð ÞK29
a9 a3 � a1ð Þ � a8 a4 � a2ð Þ
C14 ¼a3 � a1ð ÞK29 � a8K30
a9 a3 � a1ð Þ � a8 a4 � a2ð Þ ;C15 ¼ iK47;C16 ¼ iK48;
Fig. 15 Comparison of the effects of the present problem and the
temperature ratio parameter (TR) of the problem of Paul et al. (2006)
[38] at Da = 10-5, k = 0.05, Gr = 4.0, M = 0.5, F = 0.01,
Pr = 1.0, c = 6.0, [ = 0.02 and kx = 0.78
Hydromagnetic Convection Flow in a Porous Medium 421
123
C17 ¼ iK76;C18 ¼ iK77;C19 ¼ iK74;C20 ¼ iK75;
C21 ¼ iK118;C22 ¼ iK119;C23 ¼ iK116;C24 ¼ iK117;
K1 ¼A3 þ A2
A1
; K2 ¼A3 � A2
A1
; K3 ¼C2
1
3cA1
ffiffiffiffiffiffiDap ;
K4 ¼C2
2
3cA1
ffiffiffiffiffiffiDap ; K5 ¼
A3C1
cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap ; K6 ¼
�A3C2
cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap ;
K7 ¼A2C1
2cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap ; K8 ¼
�A2C2
2cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap ; K9 ¼
�A22
cA31
ffiffiffiffiffiffiDap ;
K10 ¼�2A2A3
cA31
ffiffiffiffiffiffiDap ; K11 ¼
� 2C1C2A21 þ A2
3
� �cA2
1
ffiffiffiffiffiffiDap ;
K12 ¼ K3e2ffiffiffiffiA1
pþ K4e�2
ffiffiffiffiA1
pþ K5e
ffiffiffiffiA1
p
þ K6e�ffiffiffiffiA1
pþ K7 1� 1ffiffiffiffiffi
A1
p� �
effiffiffiffiA1
p
þ K8 1þ 1ffiffiffiffiffiA1
p� �
e�ffiffiffiffiA1
pþ K9 1þ 2
A1
� �þ K10 þ K11;
K13 ¼ K3e�2ffiffiffiffiA1
pþ K4e2
ffiffiffiffiA1
p� K5e�
ffiffiffiffiA1
p
� K6effiffiffiffiA1
pþ K7 1þ 1ffiffiffiffiffi
A1
p� �
e�ffiffiffiffiA1
p
þ K8 1� 1ffiffiffiffiffiA1
p� �
effiffiffiffiA1
pþ K9 1þ 2
A1
� �� K10 þ K11;
K14 ¼GrC5
2cA1
; K15 ¼ C1
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
p� C2
ffiffiffiffiffiA1
peffiffiffiffiA1
pþ A2
A1
� 2K14;
K16 ¼C1C9
3cA1
ffiffiffiffiffiffiDap ; K17 ¼
C2C10
3cA1
ffiffiffiffiffiffiDap ;
K18 ¼1
cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap A3C9 � 2K14C1 þ
A1C1C7 þ A2C9ffiffiffiffiffiA1
p� ��
� 5
2ffiffiffiffiffiA1
p A2C9 � 2ffiffiffiffiffiA1
pK14C1
� � ;
K19 ¼1
cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap A3C10 � 2K14C2 �
A1C2C7 þ A2C10ffiffiffiffiffiA1
p� ��
þ 5
2ffiffiffiffiffiA1
p A2C10 þ 2ffiffiffiffiffiA1
pK14C2
� � ;
K20 ¼1
2cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap A2C9 � 2
ffiffiffiffiffiA1
pK14C1
� �;
K21 ¼1
2cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap A2C10 þ 2
ffiffiffiffiffiA1
pK14C2
� �;
K22 ¼ �4K14A2
3cA21
ffiffiffiffiffiffiDap ;K23 ¼ �
1
cA21
ffiffiffiffiffiffiDap A2C7 � 2K14A3ð Þ
K24 ¼ K16e2ffiffiffiffiA1
pþ K17e�2
ffiffiffiffiA1
pþ K18e
ffiffiffiffiA1
p� K19e�
ffiffiffiffiA1
p
þ K20effiffiffiffiA1
p� K21e�
ffiffiffiffiA1
p� K22 þ K23;
K25 ¼ 2K16
ffiffiffiffiffiA1
pe2ffiffiffiffiA1
p� 2K17
ffiffiffiffiffiA1
pe�2
ffiffiffiffiA1
pþ K18
ffiffiffiffiffiA1
peffiffiffiffiA1
p
þ K18effiffiffiffiA1
p� K19e�
ffiffiffiffiA1
pþ K19
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
pþ K20
ffiffiffiffiffiA1
peffiffiffiffiA1
p
þ 2K20effiffiffiffiA1
p� 2K21e�
ffiffiffiffiA1
pþ K21
ffiffiffiffiffiA1
pe�ffiffiffiffiA1
p� 3K22 þ 2K23;
K26 ¼ K16e�2ffiffiffiffiA1
pþ K17e2
ffiffiffiffiA1
p� K18e�
ffiffiffiffiA1
pþ K19e
ffiffiffiffiA1
p
þ K20e�ffiffiffiffiA1
p� K20e
ffiffiffiffiA1
pþ K22 þ K23;
K27 ¼ C3
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
p� C4
ffiffiffiffiffiA1
peffiffiffiffiA1
pþ 2K3
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
p
� 2K4
ffiffiffiffiffiA1
pe2ffiffiffiffiA1
pþ K5e�
ffiffiffiffiA1
p1�
ffiffiffiffiffiA1
p� �
þ K6effiffiffiffiA1
p1þ
ffiffiffiffiffiA1
p� �� K7e�
ffiffiffiffiA1
p1�
ffiffiffiffiffiA1
pþ 1ffiffiffiffiffi
A1
p� �
� K8effiffiffiffiA1
p1þ
ffiffiffiffiffiA1
p� 1ffiffiffiffiffi
A1
p� �
� 2K9 þ K10;
K28 ¼ 2K16
ffiffiffiffiffiA1
pe�2
ffiffiffiffiA1
p� 2K17
ffiffiffiffiffiA1
pe2ffiffiffiffiA1
p
þ K18e�ffiffiffiffiA1
p1�
ffiffiffiffiffiA1
p� �� K19e
ffiffiffiffiA1
p1þ
ffiffiffiffiffiA1
p� �
þ K20e�ffiffiffiffiA1
p ffiffiffiffiffiA1
p� 2
� �þ K21e
ffiffiffiffiA1
p ffiffiffiffiffiA1
pþ 2
� �
� 3K22 � 2K23;
K29 ¼ K26 � K24 � 2K27 þ 2K28;K30 ¼ K24 � 2K25 � K26;
K31 ¼FK3C5
4A1
; K32 ¼2FK3a12 þ TR � 1ð ÞFK16
8A1
; K33 ¼FK4C5
4A1
;
K34 ¼2FK4a13 þ TR � 1ð ÞFK17
8A1
; K35 ¼FK7C5
A1
;
K36 ¼2FK5C5 þ 2FK7a18 þ TR � 1ð ÞFK20
2A1
;
K38 ¼C1a10 þ FC3a10 þ FK5a15 þ FK7a20
A1
þ TR � 1ð Þ2A1
C9 þ FC13 �2FK18ffiffiffiffiffi
A1
p þ 6FK20
A1
� �;
K39 ¼FK8C5
A1
;
K40 ¼2FK6C5 þ 2FK8a21 þ TR � 1ð ÞFK21
2A1
þ TR � 1ð Þ2A1
FK19 þ4FK21ffiffiffiffiffi
A1
p�
;
K41 ¼2C2C5 þ 2FC4C5 þ 2FK6a16 þ 2FK8a22
2A1
þ TR � 1ð Þ2A1
C9 þ FC13 �2FK18ffiffiffiffiffi
A1
p þ 6FK20
A1
� �;
K42 ¼C2a11 þ FC4a11 þ FK6a17 þ FK8a23
A1
þ TR � 1ð Þ2A1
C10 þ FC14 þ2FK19ffiffiffiffiffi
A1
p þ 6FK21
A1
� ;
K43 ¼2FK9C5 þ TR � 1ð ÞFK22
40;
K44 ¼A2C5 þ A1 FK9C6 þ FK10C5ð Þ
12A1
þ TR � 1ð Þ24
K14 þ FK23ð Þ;
422 R. R. Singh et al.
123
K45¼A3C5þA2C6þ2FK9C5þA1 FK10C6þFK11C5ð Þ
6A1
þ TR�1ð Þ12
C7þFC11ð Þ;
K46¼A3C6þ2FK9C6þA1FK11C6
2A1
þ TR�1ð Þ4
C8þFC12ð Þ;
K47¼Pr
2K49�K50ð Þ; K48 ¼�
Pr
2K49þK50ð Þ;
K49 ¼ �K31 þ K32ð Þe�2ffiffiffiffiA1
pþ �K33 þ K34ð Þe2
ffiffiffiffiA1
p
þ �K35 þ K36 � K37ð þK38Þe�ffiffiffiffiA1
p
þ �K39 þ K40 � K41 þ K42ð ÞeffiffiffiffiA1
p
� K43 þ K44 � K45
þ K46;
K50 ¼ K31 þ K32ð Þe2ffiffiffiffiA1
pþ K33 þ K34ð Þe�2
ffiffiffiffiA1
p
þ K35 þ K36 þ K37ð þK38ÞeffiffiffiffiA1
p
þ K39 þ K40 þ K41 þ K42ð Þe�ffiffiffiffiA1
pþ K43 þ K44
þ K45 þ K46;
K51 ¼PrGrK31
6cA1
ffiffiffiffiffiA1
p ; K52 ¼PrGra32
12cA21
; K53 ¼ �PrGrK33
6cA1
ffiffiffiffiffiA1
p ;
K54 ¼PrGra33
12cA21
; K55 ¼PrGrK35
8cA1
; K56 ¼3PrGra34 þ A1K14C1
6cA1
ffiffiffiffiffiA1
p ;
K57 ¼2PrGra35 � 5
ffiffiffiffiffiA1
pK14C1 þ a45
4cA1
ffiffiffiffiffiA1
p ;
K58 ¼2PrGra36 þ 2a43 þ 17K14C1
4cA1
ffiffiffiffiffiA1
p � 5a45
4cA21
;
K59 ¼PrGrK39
8cA1
; K60 ¼3PrGra37 � A1K14C2
6cA1
ffiffiffiffiffiA1
p ;
K61 ¼2PrGra38 � 5
ffiffiffiffiffiA1
pK14C2 � a46
4cA1
ffiffiffiffiffiA1
p ;
K62 ¼2PrGra39 � 2a44 � 17K14C2
4cA1
ffiffiffiffiffiA1
p � 5a46
4cA21
;
K63 ¼ �PrGrK43
6cA1
; K64 ¼ �PrGrK44
5cA1
;
K65 ¼ �PrGra40
cA1
; K66 ¼3PrGra41 þ K14A2
3cA1
;
K67 ¼2PrGra42 þ 2K14A3 þ GrK47
2cA1
;
K68 ¼ K52 � K51ð Þe�2ffiffiffiffiA1
pþ K54 � K53ð Þe2
ffiffiffiffiA1
p
þ K55 � K56 þ K57 � K58ð Þe�2ffiffiffiffiA1
p
þ K59 � K60 þ K61 � K62ð ÞeffiffiffiffiA1
p
þ K63 � K64 þ K65 þ K66 � K67;
K69 ¼ K51 þ K52ð Þe2ffiffiffiffiA1
pþ K53 þ K54ð Þe�2
ffiffiffiffiA1
p
þ K55 þ K56 þ K57 þ K58ð Þe2ffiffiffiffiA1
p
þ K59 þ K60 þ K61 þ K62ð Þe�ffiffiffiffiA1
p
þ K63 þ K64 þ K65 � K66 � K67;
K70 ¼ 2ffiffiffiffiffiA1
pK52 � K51ð Þ þ K51
h ie�2
ffiffiffiffiA1
p
þ K53 � 2ffiffiffiffiffiA1
pK54 � K53ð Þ
h ie2ffiffiffiffiA1
p
þ �4K55 þ 3K56 � 2K57 þ K58ð Þ½þ
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiA1 K55 � K56 þ K57 � K58ð Þ
p�e�
ffiffiffiffiA1
p
þ �4K59 þ 3K60 � 2K61 þ K62ð Þ½�
ffiffiffiffiffiA1
pK59 � K60 þ K61 � K62ð Þ�e
ffiffiffiffiA1
p
� 6K63 þ 5K64 � 4K65 � 3K66 � 2K67;
K71 ¼ 2ffiffiffiffiffiA1
pK51 þ K52ð Þ þ K51
h ie2ffiffiffiffiA1
p
þ �2ffiffiffiffiffiA1
pK53 þ K54ð Þ þ K53
h ie�2
ffiffiffiffiA1
p
þ 4K55 þ 3K56 þ 2K57 þ K58ð Þ½þ
ffiffiffiffiffiA1
pK55 þ K56 þ K57 þ K58ð Þ�e
ffiffiffiffiA1
p
þ 4K59 þ 3K60 þ 2K61 þ K62ð Þ½�
ffiffiffiffiffiA1
pK59 þ K60 þ K61 þ K62ð Þ�e�
ffiffiffiffiA1
p
þ 6K63 þ 5K64 þ 4K65 � 3K66 � 2K67
K72 ¼ K68 � K69 þ 2K70;K73 ¼ K69 � 2K71 � K68;
K74 ¼a9K73 � a4 � a2ð ÞK72
a9 a3 � a1ð Þ � a8 a4 � a2ð Þ ;
K75 ¼a3 � a1ð ÞK72 � a8K73
a9 a3 � a1ð Þ � a8 a4 � a2ð Þ ;
K76 ¼K68 � K69ð Þ
2� e
ffiffiffiffiA1
p� e�
ffiffiffiffiA1
p
2
!K74 � K75ð Þ;
K77 ¼ �K69 þ K71 � a1K74 � a2K75;
K78 ¼1
cb1 þ a47 � b38 � b64 þ
2ffiffiffiffiffiffiDap a85 þ a109ð Þ
� ;
K79 ¼1
cb2 þ a48 � b39 � b65 þ
2ffiffiffiffiffiffiDap a86 þ a110ð Þ
� ;
K80 ¼1
cb3 þ a49 � b40 � b66 þ
2ffiffiffiffiffiffiDap a87 þ a111ð Þ
� ;
K81 ¼1
cb4 þ a50 � b41 � b67 þ
2ffiffiffiffiffiffiDap a88 þ a112ð Þ
� ;
K82 ¼C1K51
6cA1
ffiffiffiffiffiffiDap ;
Hydromagnetic Convection Flow in a Porous Medium 423
123
K83 ¼C2K53
6cA1
ffiffiffiffiffiffiDap ;
K84 ¼1
cb7 þ a51 � b42 � b68 þ
2ffiffiffiffiffiffiDap a89 þ a113ð Þ
� ;
K85 ¼1
cb8 þ a52 � b43 � b69 þ
2ffiffiffiffiffiffiDap a90 þ a114ð Þ
� ;
K86 ¼1
cb5 þ a53 � b44 � b70 þ
2ffiffiffiffiffiffiDap a91 þ a115ð Þ
� ;
K87 ¼1
cb6 � a54 þ b45 þ b71 þ
2ffiffiffiffiffiffiDap �a92 þ a116ð Þ
� ;
K88 ¼1
cb11 þ a55 � b46 � b72 þ
2ffiffiffiffiffiffiDap a93 þ a117ð Þ
� ;
K89 ¼1
cb12 þ a56 � b47 � b73 þ
2ffiffiffiffiffiffiDap a94 þ a118ð Þ
� ;
K90 ¼1
cb9 þ a57 � b48 � b74 þ
2ffiffiffiffiffiffiDap a95 þ a119ð Þ
� ;
K91 ¼1
cb10 � a58 � b49 þ b75 þ
2ffiffiffiffiffiffiDap �a96 þ a120ð Þ
� ;
K92 ¼2
cffiffiffiffiffiffiDap a97 þ a121ð Þ; K93 ¼
2
cffiffiffiffiffiffiDap a98 þ a122ð Þ;
K94 ¼1
cb13 þ a59 � b50 � b76 þ
2ffiffiffiffiffiffiDap a99 þ a123ð Þ
� ;
K95 ¼1
cb14 þ a60 � b51 � b77 þ
2ffiffiffiffiffiffiDap �a100 þ a124ð Þ
� ;
K96 ¼C1K55
3cA1
ffiffiffiffiffiffiDap ;
K97 ¼C2K59
3cA1
ffiffiffiffiffiffiDap ;
K98 ¼1
cb15 � b52 � b78 þ
2ffiffiffiffiffiffiDap a101 þ a125ð Þ
� ;
K99 ¼1
cb16 � b53 � b79 þ
2ffiffiffiffiffiffiDap �a102 þ a126ð Þ
� ;
K100 ¼1
c�b54 þ
2ffiffiffiffiffiffiDap a103 þ a127ð Þ
� ;
K101 ¼1
c�b55 þ
2ffiffiffiffiffiffiDap �a104 þ a128ð Þ
� ;
K102 ¼A2K55 þ 6
ffiffiffiffiffiA1
pC1K63
6cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap
� �;
K103 ¼6ffiffiffiffiffiA1
pC2K63 � A2K59
6cA1
ffiffiffiffiffiffiffiffiffiffiffiA1Dap
� �;
K104 ¼12A2K63
7cA21
ffiffiffiffiffiffiDap ; K105 ¼
b103 þ b128ð Þ15cA1
ffiffiffiffiffiffiDap ;
K106 ¼2 a105 þ a129ð Þ
cffiffiffiffiffiffiDap ;
K107 ¼1
cb19 þ a61 � b56 � b80 �
2ffiffiffiffiffiffiDap a106 þ a130ð Þ
� ;
K108 ¼1
cb18 þ a62 � b57 � b81 �
2ffiffiffiffiffiffiDap a107 þ a131ð Þ
� ;
K109 ¼1
cb17 þ a63 � b58 � b82 �
2ffiffiffiffiffiffiDap a108 þ a132ð Þ
� ;
K110 ¼ K78 � K82ð Þe�3ffiffiffiffiA1
pþ K79 � K83ð Þe3
ffiffiffiffiA1
p
þ K80 � K84ð þ K88
� K92 þ K96Þe�2ffiffiffiffiA1
p
þ K81 � K85ð þ K89 � K93 þ K97Þe2ffiffiffiffiA1
p
þ �K86 þ K90ð � K94 þ K98 � K100 þ K102Þe�ffiffiffiffiA1
p
þ �K87 þ K91ð � K95 þ K99 � K101 þ K102ÞeffiffiffiffiA1
p
þ K104 � K105 þ K106 þ K107 � K108 þ K109;
K111 ¼ K78 þ K82ð Þe3ffiffiffiffiA1
pþ K79 þ K83ð Þe�3
ffiffiffiffiA1
p
þ K80 þ K84ð þ K88
þ K92 þ K96Þe2ffiffiffiffiA1
p
þ K81 þ K85ð þ K89 þ K93 þ K97Þe�2ffiffiffiffiA1
p
þ K86 þ K90ð þ K94 þ K98 þ K100 þ K102ÞeffiffiffiffiA1
p
þ K87 þ K91ð þ K95 þ K99 þ K101 þ K103Þe�ffiffiffiffiA1
p
� K104 � K105 � K106 þ K107 þ K108 þ K109;
K112 ¼ 3ffiffiffiffiffiA1
pK78 � 3
ffiffiffiffiffiA1
pK82 þ K82
� �e�3
ffiffiffiffiA1
p
þ �3ffiffiffiffiffiA1
pK79 þ 3
ffiffiffiffiffiA1
pK83 þ K83
� �e3ffiffiffiffiA1
p
þ 2ffiffiffiffiffiA1
pK80�
�2ffiffiffiffiffiA1
pK84 þ 2
ffiffiffiffiffiA1
pK88
� 2ffiffiffiffiffiA1
pK92 þ 2
ffiffiffiffiffiA1
pK96 þ K84 � 2K88 þ 3K92 � 4K96
�e�2
ffiffiffiffiA1
p
þ �2ffiffiffiffiffiA1
pK81
�þ 2
ffiffiffiffiffiA1
pK85 � 2
ffiffiffiffiffiA1
pK89 þ 2
ffiffiffiffiffiA1
pK93
� 2ffiffiffiffiffiA1
pK97þK85 � 2K89 þ 3K93 � 4K97Þe2
ffiffiffiffiA1
p
þ �ffiffiffiffiffiA1
pK86
�þ
ffiffiffiffiffiA1
pK90 �
ffiffiffiffiffiA1
pK94 þ
ffiffiffiffiffiA1
pK98
�ffiffiffiffiffiA1
pK100 þ
ffiffiffiffiffiA1
pK102 þ K86 � 2K90
þ 3K94 � 4K98 þ 5K100 � 6K102Þe�ffiffiffiffiA1
p
þffiffiffiffiffiA1
pK87 �
ffiffiffiffiffiA1
pK91
�þ
ffiffiffiffiffiA1
pK95 �
ffiffiffiffiffiA1
pK99
þffiffiffiffiffiA1
pK101 �
ffiffiffiffiffiA1
pK103 þ K87 � 2K91
þ 3K95 � 4K99 þ 5K101 � 6K103ÞeffiffiffiffiA1
p
� 7K104 þ 6K105 � 5K106 � 4K107
þ 3K108 � 2K109;
424 R. R. Singh et al.
123
K113 ¼ 3ffiffiffiffiffiA1
pK78 þ 3
ffiffiffiffiffiA1
pK82 þ K82
� �e3ffiffiffiffiA1
pþ �3
ffiffiffiffiffiA1
pK79
�
� 3ffiffiffiffiffiA1
pK83 þ K83
�e�3
ffiffiffiffiA1
pþ 2
ffiffiffiffiffiA1
pK80þ
�2ffiffiffiffiffiA1
pK84 þ 2
ffiffiffiffiffiA1
pK88
þ 2ffiffiffiffiffiA1
pK92 þ 2
ffiffiffiffiffiA1
pK96 þ K84 þ 2K88 þ 3K92 þ 4K96
�e2ffiffiffiffiA1
p
þ �2ffiffiffiffiffiA1
pK81
�� 2
ffiffiffiffiffiA1
pK85 � 2
ffiffiffiffiffiA1
pK89 � 2
ffiffiffiffiffiA1
pK93 � 2
ffiffiffiffiffiA1
pK97
þK85 þ 2K89 þ 3K93 þ 4K97Þe�2ffiffiffiffiA1
pþ
ffiffiffiffiffiA1
pK86 þ
ffiffiffiffiffiA1
pK90
�
þffiffiffiffiffiA1
pK94 þ
ffiffiffiffiffiA1
pK98 þ
ffiffiffiffiffiA1
pK100 þ
ffiffiffiffiffiA1
pK102 þ K86 þ 2K90
þ 3K94 þ 4K98 þ 5K100 þ 6K102ÞeffiffiffiffiA1
pþ �
ffiffiffiffiffiA1
pK87
�
�ffiffiffiffiffiA1
pK91 �
ffiffiffiffiffiA1
pK95 �
ffiffiffiffiffiA1
pK99 �
ffiffiffiffiffiA1
pK101 �
ffiffiffiffiffiA1
pK103
þK87 þ 2K91 þ 3K95 þ 4K99 þ 5K101 þ 6K103Þe�ffiffiffiffiA1
p
� 7K104 � 6K105 � 5K106 þ 4K107 þ 3K108 þ 2K109;
K114 ¼ K110 � K111 þ 2K112;
K115 ¼ K111 � 2K113 � K110;
K116 ¼a9K115 � a4 � a2ð ÞK114
a9 a3 � a1ð Þ � a8 a4 � a1ð Þ ;
K117 ¼a3 � a1ð ÞK114 � a8K115
a9 a3 � a1ð Þ � a8 a4 � a2ð Þ ;
K118 ¼1
2K110 � K111ð Þ � 1
2effiffiffiffiA1
p� e�
ffiffiffiffiA1
p� �K116 � K117ð Þ;
K119 ¼ �a1K116 � a2K117 þ K113 � K111;
a1 ¼ effiffiffiffiA1
p1�
ffiffiffiffiffiA1
p� �; a2 ¼ e�
ffiffiffiffiA1
p1þ
ffiffiffiffiffiA1
p� �;
a3 ¼ e�ffiffiffiffiA1
pþ
ffiffiffiffiffiA1
peffiffiffiffiA1
p;
a4 ¼ effiffiffiffiA1
p�
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
p; a5 ¼
2
effiffiffiffiA1
p� e�
ffiffiffiffiA1
p ;
a6 ¼ a5
ffiffiffiffiffiA1
pe�
ffiffiffiffiA1
p� 1;
a7 ¼ a5
ffiffiffiffiffiA1
peffiffiffiffiA1
p� 1; a8 ¼ e
ffiffiffiffiA1
p� e�
ffiffiffiffiA1
p1þ 2
ffiffiffiffiffiA1
p� �;
a9 ¼ e�ffiffiffiffiA1
p� e
ffiffiffiffiA1
p1� 2
ffiffiffiffiffiA1
p� �; a10 ¼ C6 �
2C5ffiffiffiffiffiA1
p ;
a11 ¼ C6 þ2C5ffiffiffiffiffi
A1
p ;
a12 ¼ C6 �C5ffiffiffiffiffiA1
p ; a13 ¼ C6 þC5ffiffiffiffiffiA1
p ; a14 ¼ C6 �4C5ffiffiffiffiffi
A1
p ;
a15 ¼6C5 � 2
ffiffiffiffiffiA1
pC6
A1
; a16 ¼ C6 þ4C5ffiffiffiffiffi
A1
p ;
a17 ¼6C5 þ 2
ffiffiffiffiffiA1
pC6
A1
;
a18 ¼ C6 �7C5ffiffiffiffiffi
A1
p ; a19 ¼22C5
A1
� 5C6ffiffiffiffiffiA1
p ;
a20 ¼8C�6
A1
� 30C5
A1
ffiffiffiffiffiA1
p ;
a21 ¼ C6 þ7C5ffiffiffiffiffi
A1
p ; a22 ¼22C5
A1
þ 5C6ffiffiffiffiffiA1
p ;
a23 ¼8C6
A1
þ 30C5
A1
ffiffiffiffiffiA1
p ;
a24 ¼ K31 þ 2ffiffiffiffiffiA1
pK32;
a25 ¼ K33 � 2ffiffiffiffiffiA1
pK34;
a26 ¼ 3K35 þffiffiffiffiffiA1
pK36;
a27 ¼ 2K36 þ 2ffiffiffiffiffiA1
pK37; a28 ¼ K37 þ K38;
a29 ¼ 3K39 �ffiffiffiffiffiA1
pK40;
a30 ¼ 2K40 �ffiffiffiffiffiA1
pK41; a31 ¼ K41 þ K42;
a32 ¼ a24 �14
3K31
a33 ¼ a25 �14
3K33; a34 ¼
1
3a26 �
15
3K35
� �;
a35 ¼1
2a27 þ
51K35
2ffiffiffiffiffiA1
p � 5a26ffiffiffiffiffiA1
p� �
;
a36 ¼ a28 �5a27
2ffiffiffiffiffiA1
p þ 17a26
2A1
� 147K35
4A1
;
a37 ¼ �1
3a29 �
15
2K39
� �;
a38 ¼ �1
2a30 �
51K39
2ffiffiffiffiffiA1
p þ 5a29ffiffiffiffiffiA1
p� �
;
a39 ¼ � a31 �5a30
2ffiffiffiffiffiA1
p þ 17a29
2A1
� 147K39
4A1
� �;
a40 ¼1
4K45 þ
20
A1
K43
� �;
a41 ¼1
3K46 þ
12
A1
K44
� �;
a42 ¼3A1K45 þ 60K43
A21
� �;
a43 ¼ A3C9 � 2K14C1 � A1C1C8;
a44 ¼ A3C10 � 2K14C2 � A1C2C8;
a45 ¼ A2C9 � A1C1C7; a46 ¼ A2C10 � A1C2C7;
a47 ¼b20
72A21
;
a48 ¼b21
72A21
; a49 ¼3ffiffiffiffiffiA1
pb22 � 7b26 þ 3
ffiffiffiffiffiA1
pb30b37
� �36A2
1
ffiffiffiffiffiA1
p ;
a50 ¼3ffiffiffiffiffiA1
pb23 þ 7b27 þ 3
ffiffiffiffiffiA1
pb31b37
� �36A2
1
ffiffiffiffiffiA1
p ;
a51 ¼3ffiffiffiffiffiA1
pb26 � 14b30
� �36A2
1
ffiffiffiffiffiA1
p ;
Hydromagnetic Convection Flow in a Porous Medium 425
123
a52 ¼3ffiffiffiffiffiA1
pb27 þ 14b31
� �36A2
1
ffiffiffiffiffiA1
p ; a53
¼2A1b24 � 5
ffiffiffiffiffiA1
pb28 þ 17b32þ
� �4A2
1
ffiffiffiffiffiA1
p ;
a54 ¼2A1b25 þ 5
ffiffiffiffiffiA1
pb29 þ 17b33
� �4A2
1
ffiffiffiffiffiA1
p ; a55 ¼b30
12A21
;
a56 ¼b31
12A21
;
a57 ¼ffiffiffiffiffiA1
pb28 � 5b32
� �4A2
1
; a58 ¼ffiffiffiffiffiA1
pb29 þ 5b33
� �4A2
1
;
a59 ¼b32
6A1
ffiffiffiffiffiA1
p ;
a60 ¼ �b33
6A1
ffiffiffiffiffiA1
p ; a61 ¼ �b34
12A1
; a62 ¼ �b35
6A1
;
a63 ¼ �2b34 þ A1b36ð Þ
2A21
; a64 ¼ 4A1C9K3;
a65 ¼ 4A1C10K4;
a66 ¼ 4A1C8K3 þ A1C3C9 þ 2ffiffiffiffiffiA1
pC9K5;
a67 ¼ 4A1C8K4 þ A1C4C10 � 2ffiffiffiffiffiA1
pC10K6;
a68 ¼ 4A1C10K3 þ A1C3C8 þ 2ffiffiffiffiffiA1
pC8K6 þ 2C9K9;
a69 ¼ 4A1C9K4 þ A1C4C8 � 2ffiffiffiffiffiA1
pC8K6 þ 2C10K9;
a70 ¼ 4A1C7K3 þffiffiffiffiffiA1
pC9K5 þ 3
ffiffiffiffiffiA1
pC9K7; a71
¼ 4A1C7K4 þffiffiffiffiffiA1
pC10K6 � 3
ffiffiffiffiffiA1
pC10K8;
a72 ¼ A1C3C7 þ 2ffiffiffiffiffiA1
pC7K5 þ
ffiffiffiffiffiA1
pC8K5 þ 3
ffiffiffiffiffiA1
pC8K7;
a73 ¼ A1C4C7 � 2ffiffiffiffiffiA1
pC7K6 þ
ffiffiffiffiffiA1
pC8K6 � 3
ffiffiffiffiffiA1
pC8K8;
a74 ¼ A1C9K7 � 4A1K3K14; a75 ¼ A1C10K8 þ 4A1K4K14;
a76 ¼ A1C8K7 � A1C3K14 þffiffiffiffiffiA1
pC7K5 þ 3
ffiffiffiffiffiA1
pC7K7
� 2ffiffiffiffiffiA1
pK5K14;
a77 ¼ �A1C8K8 � A1C4K14 þffiffiffiffiffiA1
pC7K6 þ 2
ffiffiffiffiffiA1
pK6K14;
a78 ¼ A1C7K7 �ffiffiffiffiffiA1
pK5K14 � 3
ffiffiffiffiffiA1
pK7K14; a79
¼ A1C7K8 þffiffiffiffiffiA1
pK6K14 � 3
ffiffiffiffiffiA1
pK8K14;
a80 ¼ �A1K7K14; a81 ¼ A1K8K14; a82
¼ A1C9K8 � A1C10K7 þ 2K9K14;
a83 ¼ffiffiffiffiffiA1
pC9K6 � 3
ffiffiffiffiffiA1
pC9K8 þ
ffiffiffiffiffiA1
pC10K5
þ 3ffiffiffiffiffiA1
pC10K7 þ 2C7K9;
a84 ¼ A1C4C9 þ A1C3C10 þ 2C8K9 þ 2ffiffiffiffiffiA1
pC9K5
� 2ffiffiffiffiffiA1
pC9K6;
a85 ¼b83
72A21
� 17C1K51
216A1
ffiffiffiffiffiA1
p ; a86 ¼b84
72A21
þ 17C2K53
216A1
ffiffiffiffiffiA1
p ;
a87 ¼b85
12A21
� 7b89
36A21
ffiffiffiffiffiA1
p þ b37b93
12A21
� 239b97
108A31
ffiffiffiffiffiA1
p
þ 6529C1K55
648A31
;
a88 ¼b86
12A21
þ 7b90
36A21
ffiffiffiffiffiA1
p þ b37b93
12A21
þ 239b97
108A31
ffiffiffiffiffiA1
p
þ 6529C2K59
648A31
;
a89 ¼b89
12A21
� 7b93
18A21
ffiffiffiffiffiA1
p þ 127b97
72A31
� 239C1K55
27A21
ffiffiffiffiffiA1
p ;
a90 ¼b90
12A21
þ 7b94
18A21
ffiffiffiffiffiA1
p þ 127b98
72A31
þ 239C2K59
27A21
ffiffiffiffiffiA1
p ;
a91 ¼b87
2A1
ffiffiffiffiffiA1
p � 5b91
4A21
þ 17b95
4A21
ffiffiffiffiffiA1
p � 147b99
8A31
þ 387b101
4A31
ffiffiffiffiffiA1
p
� 4815A2K55
8A41
;
a92 ¼b88
2A1
ffiffiffiffiffiA1
p þ 5b92
4A21
þ 17b96
4A21
ffiffiffiffiffiA1
p þ 147b101
8A31
þ 387b102
4A31
ffiffiffiffiffiA1
p
þ 4815A2K59
8A41
;
a93 ¼b93
12A21
� 7b97
12A21
ffiffiffiffiffiA1
p þ 127C1K55
36A21
;
a94 ¼b94
12A21
þ 7b98
12A21
ffiffiffiffiffiA1
p þ 127C2K59
36A21
;
a95 ¼b91
4A1
ffiffiffiffiffiA1
p � 5b95
4A21
þ 51b99
8A21
ffiffiffiffiffiA1
p � 147b101
4A31
þ 1935A2K55
8A31
ffiffiffiffiffiA1
p ;
a96 ¼b92
4A1
ffiffiffiffiffiA1
p þ 5b96
4A21
þ 51b100
8A21
ffiffiffiffiffiA1
p þ 147b102
4A31
þ 1935A2K59
8A31
ffiffiffiffiffiA1
p ;
a97 ¼b97
12A21
� 7C1K55
9A1
ffiffiffiffiffiA1
p ; a98 ¼b98
12A21
þ 7C2K59
9A1
ffiffiffiffiffiA1
p ;
a99 ¼b95
6A1
ffiffiffiffiffiA1
p � 5b99
4A21
þ 17b101
2A21
ffiffiffiffiffiA1
p � 245A2K55
4A31
;
a100 ¼b96
6A1
ffiffiffiffiffiA1
p þ 5b100
4A21
þ 17b102
2A21
ffiffiffiffiffiA1
p þ 245A2K59
4A31
;
a101 ¼b99
8A1
ffiffiffiffiffiA1
p � 5b101
4A21
þ 85A2K55
4A21
ffiffiffiffiffiA1
p ;
a102 ¼b100
8A1
ffiffiffiffiffiA1
p þ 5b102
4A21
þ 85A2K59
4A21
ffiffiffiffiffiA1
p ;
a103 ¼b101
10A1
ffiffiffiffiffiA1
p � 5A2K55
4A21
; a104 ¼b102
10A1
ffiffiffiffiffiA1
p þ 5A2K59
4A21
;
426 R. R. Singh et al.
123
a105 ¼30A2K63
A31
þ b104
20A1
; a106 ¼b103
A21
þ b105
12A1
;
a107 ¼600A2K63
A41
þ b104
A21
þ b106
6A1
;
a108 ¼12b103
A31
þ b105
A21
þ b107
2A1
;
a109 ¼b108
72A21
� 17C1K51
432A21
ffiffiffiffiffiA1
p ; a110 ¼b109
72A21
þ 17C2K53
432A21
ffiffiffiffiffiA1
p ;
a111 ¼b110
12A21
� 7b114
36A21
ffiffiffiffiffiA1
p þ b37b118
12A21
� 239b122
108A31
ffiffiffiffiffiA1
p
þ 6529C1K55
648A31
;
a112 ¼b111
12A21
þ 7b115
36A21
ffiffiffiffiffiA1
p þ b37b119
12A21
þ 239b123
108A31
ffiffiffiffiffiA1
p
þ 6529C2K59
648A31
;
a113 ¼b114
12A21
� 7b118
18A21
ffiffiffiffiffiA1
p þ 127b122
72A31
� 239C1K55
27A21
ffiffiffiffiffiA1
p ;
a114 ¼b115
12A21
þ 7b119
18A21
ffiffiffiffiffiA1
p þ 127b123
72A31
þ 239C2K59
27A21
ffiffiffiffiffiA1
p ;
a115 ¼b112
2A1
ffiffiffiffiffiA1
p þ 5b116
4A21
þ 17b121
4A21
ffiffiffiffiffiA1
p � 147b124
8A31
þ 387b126
4A31
ffiffiffiffiffiA1
p
� 14445C1K63
4A31
ffiffiffiffiffiA1
p ;
a116 ¼b113
2A1
ffiffiffiffiffiA1
p � 5b117
4A21
� 17b121
4A21
ffiffiffiffiffiA1
p þ 147b125
8A31
þ 387b127
4A31
ffiffiffiffiffiA1
p
þ 14445C2K63
4A31
ffiffiffiffiffiA1
p ;
a117 ¼b118
12A21
� 7b122
12A21
ffiffiffiffiffiA1
p þ 127C1K55
36A21
;
a118 ¼b119
12A21
þ 7b123
12A21
ffiffiffiffiffiA1
p þ 127C2K59
36A21
;
a119 ¼ �b116
4A1
ffiffiffiffiffiA1
p � 5b120
4A21
þ 51b124
8A21
ffiffiffiffiffiA1
p � 147b126
4A31
þ 5805C1K63
4A31
;
a120 ¼ �b117
4A1
ffiffiffiffiffiA1
p � 5b121
4A21
þ 51b125
8A21
ffiffiffiffiffiA1
p þ 147b127
4A31
þ 5805C2K63
4A31
;
a121 ¼b122
12A21
� 7C1K55
9A1
ffiffiffiffiffiA1
p ; a122 ¼b123
12A21
þ 7C2K59
9A1
ffiffiffiffiffiA1
p ;
a123 ¼b120
6A1
ffiffiffiffiffiA1
p � 5b124
4A21
þ 17b126
2A21
ffiffiffiffiffiA1
p � 735C1K63
2A21
ffiffiffiffiffiA1
p ;
a124 ¼ �b121
6A1
ffiffiffiffiffiA1
p þ 5b125
4A21
þ 17b127
2A21
ffiffiffiffiffiA1
p þ 735C2K63
2A21
ffiffiffiffiffiA1
p ;
a125 ¼b124
8A1
ffiffiffiffiffiA1
p � 5b126
4A21
þ 255C1K63
4A21
;
a126 ¼b125
8A1
ffiffiffiffiffiA1
p þ 5b127
4A21
þ 255C2K63
4A21
;
a127 ¼b126 � 75C1K63ð Þ
10A1
ffiffiffiffiffiA1
p ; a128 ¼b127 þ 75C2K63ð Þ
10A1
ffiffiffiffiffiA1
p ;
a129 ¼6A2K63
A31
þ b129
20A1
; a130 ¼12b128 þ A1b130ð Þ
12A1
;
a131 ¼120A2K63
A41
þ b129
A21
þ b131
6A1
;
a132 ¼12b128
A31
þ b130
A21
þ b132
2A1
;
b1 ¼C1K16
18A1
; b2 ¼C2K17
18A1
;
b3 ¼1
12A21
A1C1C13 þ 2ffiffiffiffiffiA1
pC1K18 þ 2C1K20 þ 4A3K16
� �
� 7
36A21
ffiffiffiffiffiA1
p 4ffiffiffiffiffiA1
pC1K20 þ A1C1K18 þ 4A2K16
� �
þ 127C1K20
216A21
;
b4 ¼1
12A21
A1C2C14 þ 2ffiffiffiffiffiA1
pC2K19 � 2C2K21 þ 4A3K17
� �
þ 7
36A21
ffiffiffiffiffiA1
p 4ffiffiffiffiffiA1
pC2K21 � A1C2K19 þ 4A2K17
� �� 127C2K21
216A21
;
b5 ¼1
2A1
ffiffiffiffiffiA1
p 2C1K23 þ 4C2A1K16 þ A3C13 þ2A3K18ffiffiffiffiffi
A1
p þ 2A3K20
A1
� �
� 5
4A21
�6K22C1 þ A3C13 þ2A3K18ffiffiffiffiffi
A1
p þ 2A3K20
A1
þ A3K18
� �
þ 17
4A21
ffiffiffiffiffiA1
p A2K18 þ4A2K20ffiffiffiffiffi
A1
p þ A3K20
� �� 147A2K20
8A31
;
b6 ¼ �1
2A1
ffiffiffiffiffiA1
p 2C2K23 þ 4C1A1K17 þ A3C14 þ2A3K19ffiffiffiffiffi
A1
p � 2A3K21
A1
� �
� 5
4A21
�6K22C2 þ A2C14 þ2A2K19ffiffiffiffiffi
A1
p � 2A2K21
A1
þ 4A3K21ffiffiffiffiffiA1
p � A3K19
� �
� 17
4A21
ffiffiffiffiffiA1
p �A2K19 þ4A2K21ffiffiffiffiffi
A1
p � A3K21
� �þ 147A2K21
8A31
;
b7 ¼1
12A21
4C1K20
ffiffiffiffiffiA1
pþ A1C1K18 þ 4A2K16
� �
� 7C1K20
18A1
ffiffiffiffiffiA1
p ;
b8 ¼1
12A21
4C2K21
ffiffiffiffiffiA1
p� A1C2K19 þ 4A2K17
� �
� 7C2K21
18A1
ffiffiffiffiffiA1
p ;
Hydromagnetic Convection Flow in a Porous Medium 427
123
b9 ¼1
4A1
ffiffiffiffiffiA1
p �6K22C1 þ A3C13 þ2A3K18ffiffiffiffiffi
A1
p�
þ 2A3K20
A1
þ 4A3K20ffiffiffiffiffiA1
p þ A3K18
� 5
4A21
A2K18 þ4A2K20ffiffiffiffiffi
A1
p þ A3K20
� �þ 51A2K20
8A21
ffiffiffiffiffiA1
p ;
b10 ¼ �1
4A1
ffiffiffiffiffiA1
p �6K22C2 þ A2C14 þ2A2K19ffiffiffiffiffi
A1
p�
� 2A2K21
A1
þ 4A3K21ffiffiffiffiffiA1
p � A3K19
þ 5
4A21
A2K19 �4A2K21ffiffiffiffiffi
A1
p þ A3K21
� �þ 51A2K22
8A21
ffiffiffiffiffiA1
p ;
b11 ¼C1K20
12A1
; b12 ¼ �C2K21
12A1
;
b13 ¼1
6A1
ffiffiffiffiffiA1
p A2K18 þ4A2K20ffiffiffiffiffi
A1
p þ A3K20
� �� 5A2K20
4A21
;
b14 ¼1
6A1
ffiffiffiffiffiA1
p A2K19 �4A2K21ffiffiffiffiffi
A1
p þ A3K21
� �þ 5A2K21
4A21
;
b15 ¼A2K20
8A1
ffiffiffiffiffiA1
p ; b16 ¼A2K21
8A1
ffiffiffiffiffiA1
p ;
b17 ¼1
A21
A1C1K21 � A1C2K20 þ6A2K22ffiffiffiffiffi
A1
p�
� 1
2A1
A1C1C14 þ 2ffiffiffiffiffiA1
phC1K19
� 2C1K21 þ A1C2C13 þ 2ffiffiffiffiffiA1
pC2K18
þ 2C2K20þ2A3K23
A1
;
b18 ¼ �1
6A1
4ffiffiffiffiffiA1
pC1K21 � A1C1K19 þ A1C2K18
h
þ 4ffiffiffiffiffiA1
pC2K20 þ
2A2K23
A1
;
b19 ¼1
12A1
A1C1K21 � A1C2K20 þ6A2K22
A1
� ;
b20 ¼ A1K3C9;
b21 ¼ A1K4C10; b22 ¼ A1C3C9 � 2K14K3;
b23 ¼ A1C4C10 � 2K14K4;
b24 ¼ 2K9C9 þ A1K11C9 þ A1K3C10 � 2K14C3;
b25 ¼ A1K4C9 þ 2K9C10 þ A1K11C10 � 2K14C4;
b26 ¼ A1K5C9 �ffiffiffiffiffiA1
pK7C9; b27 ¼ A1K6C10 þ
ffiffiffiffiffiA1
pK8C10;
b28 ¼ A1K10C9 � 2K14K5 þ2K14K7ffiffiffiffiffi
A1
p ;
b29 ¼ A1K10C10 � 2K14K6 �2K14K8ffiffiffiffiffi
A1
p ;
b30 ¼ A1K7C9; b31 ¼ A1K8C10; b32 ¼ A1K9C9 � 2K14K7;
b33 ¼ A1K9C10 � 2K14K8;
b34 ¼ A1K8C9 þ A1K7C10 � 2K14C9;
b35 ¼ A1K6C9 þ A1K5C10 þffiffiffiffiffiA1
pK8C9 �
ffiffiffiffiffiA1
pK7C10;
b36 ¼ A1C4C9 þ A1C3C10 �4K14K9
A1
� 2K14K11;
b37 ¼127
18A1
; b38 ¼a64
72A21
; b39 ¼a65
72A21
;
b40 ¼3ffiffiffiffiffiA1
pa66 � 7a70 þ 3
ffiffiffiffiffiA1
pb37a74
36A21
ffiffiffiffiffiA1
p ;
b41 ¼3ffiffiffiffiffiA1
pa67 þ 7a71 � 3
ffiffiffiffiffiA1
pb37a75
36A21
ffiffiffiffiffiA1
p ;
b42 ¼3ffiffiffiffiffiA1
pa70 � 14a74
36A21
ffiffiffiffiffiA1
p ;
b43 ¼3ffiffiffiffiffiA1
pa71 � 14a75
36A21
ffiffiffiffiffiA1
p ;
b44 ¼4A2
1a68 � 10A1
ffiffiffiffiffiA1
pa72 þ 34A1a76 � 147
ffiffiffiffiffiA1
pa78 � 774a80
8A31
ffiffiffiffiffiA1
p ;
b45 ¼4A2
1a69 þ 10A1
ffiffiffiffiffiA1
pa73 þ 34A1a77 � 147
ffiffiffiffiffiA1
pa79 þ 774a81
8A31
ffiffiffiffiffiA1
p ;
b46 ¼a74
12A21
; b47 ¼ �a75
12A21
;
b48 ¼2A1
ffiffiffiffiffiA1
pa72 � 10A1a76 þ 51
ffiffiffiffiffiA1
pa78 þ 294a80
8A31
;
b49 ¼ �2A1
ffiffiffiffiffiA1
pa73 þ 10A1a77 � 51
ffiffiffiffiffiA1
pa79 þ 294a81
� �8A3
1
;
b50 ¼2ffiffiffiffiffiA1
pa76 � 15a78 � 102a80
12A21
;
b51 ¼�2
ffiffiffiffiffiA1
pa77 þ 15a79 � 102a81
12A21
;
b52 ¼ffiffiffiffiffiA1
pa78 þ 10a80
8A21
; b53 ¼ffiffiffiffiffiA1
pa79 � 10a81
8A21
;
b54 ¼ �a80
10A1
ffiffiffiffiffiA1
p ;
428 R. R. Singh et al.
123
b55 ¼ �a81
10A1
ffiffiffiffiffiA1
p ; b56 ¼a82
12A1
; b57 ¼ �a83
6A1
;
b58 ¼2a82 � A1a84
2A21
;
b59 ¼ A1C1C12 þ A1C2K6; b60 ¼ A1C2C12 þ A1C1K17;
b61 ¼ A1C2K20 � A1C1K21; b62 ¼ A1C2K18 � A1C1K19;
b63 ¼ A1C1C14 þ A1C2C13; b64 ¼C1K16
72A1
; b65 ¼C2K17
72A1
;
b66 ¼3ffiffiffiffiffiA1
pC1C13 � 7C1K18 þ 3
ffiffiffiffiffiA1
pC1K20b37
36A1
ffiffiffiffiffiA1
p ;
b67 ¼3ffiffiffiffiffiA1
pC2C14 � 7C2K19 � 3
ffiffiffiffiffiA1
pC2K21b37
36A1
ffiffiffiffiffiA1
p ;
b68 ¼3ffiffiffiffiffiA1
pC1K18 � 14C1K20
36A1
ffiffiffiffiffiA1
p ;
b69 ¼3ffiffiffiffiffiA1
pC2K19 þ 14C2K21
36A1
ffiffiffiffiffiA1
p ;
b70 ¼4ffiffiffiffiffiA1
pb59 � 10A1C1C11 þ 34
ffiffiffiffiffiA1
pC1K23 þ 147C1K22
8A21
;
b71 ¼4ffiffiffiffiffiA1
pb60 þ 10A1C2C11 þ 34
ffiffiffiffiffiA1
pC2K23 � 147C2K22
8A21
;
b72 ¼C1K21
12A1
; b73 ¼ �C2K21
12A1
;
b74 ¼2A1C1C11 � 5
ffiffiffiffiffiA1
pC1K23 � 51C1K22
8A1
ffiffiffiffiffiA1
p ;
b75 ¼2A1C2C11 þ 5
ffiffiffiffiffiA1
pC2K23 � 51C2K22
8A1
ffiffiffiffiffiA1
p ;
b76 ¼2ffiffiffiffiffiA1
pC1K23 þ 15C1K22
12A1
;
b77 ¼15C2K22 � 2
ffiffiffiffiffiA1
pC2K23
12A1
; b78 ¼ �C1K22
8ffiffiffiffiffiA1
p ;
b79 ¼C2K22
8ffiffiffiffiffiA1
p ;
b80 ¼ �b61
12A1
; b81 ¼ �b62
6A1
; b82 ¼ �2b61 þ A1b63ð Þ
2A21
;
b83 ¼ 4ffiffiffiffiffiA1
pC1K51 þ 4A1C1K52;
b84 ¼ 4A1C2K54 � 4
ffiffiffiffiffiA1
pC
2K53;
b85 ¼ 2ffiffiffiffiffiA1
pC1K58 þ 2C1K57 þ A1C1K74 þ
4A3K51ffiffiffiffiffiA1
p
þ 4A3K52
b86 ¼ 2C2K61 � 2ffiffiffiffiffiA1
pC2K62 þ A1C2K75 þ 4A3K54 �
4A3K53ffiffiffiffiffiA1
p� �
;
b87 ¼2A3K58ffiffiffiffiffi
A1
p þ 2A3K57
A1
þ A3K74 � 2C1K67 þ 4C2
ffiffiffiffiffiA1
pK51
þ 4C2A1K52;
b88 ¼ 4A1C1K54 � 4C1
ffiffiffiffiffiA1
pK53 þ
2A3K61
A1
� 2A3K62ffiffiffiffiffiA1
p
þ A3K75 � 2C2K67;
b89 ¼ A1C1K58 þ 4ffiffiffiffiffiA1
pC1K57 þ 6C1K56 þ
4A2K51ffiffiffiffiffiA1
p
þ 4A2K52 þ 4A3K51;
b90 ¼ A1C2K62 � 4ffiffiffiffiffiA1
pC2K61 þ 6C2K60 þ 4A2K54
� 4A2K53ffiffiffiffiffiA1
p þ 4A3K53;
b91 ¼ 4A1C2K51 þ2A2K58ffiffiffiffiffi
A1
p�
þ 2A2K57
A1
þ A2K74 þ A3K58
þ 4A3K57ffiffiffiffiffiA1
p þ 6A3K56
A1
� 6C1K66
�;
b92 ¼ 4A1C1K53 �2A2K62ffiffiffiffiffi
A1
p�
þ 2A2K61
A1
þ A2K75 þ A3K62
� 4A3K61ffiffiffiffiffiA1
p þ 6A3K60
A1
� 6C2K66
�;
b93 ¼ A1C1K57 þ 6ffiffiffiffiffiA1
pC1K56 þ 12C1K55 þ 4A2K51;
b94 ¼ A1C2K61 � 6ffiffiffiffiffiA1
pC2K60 � 12C2K59 þ 4A2K53;
b95 ¼ 12C1K65 þ A2K58 þ4A2K57ffiffiffiffiffi
A1
p þ 6A2K56
A1
þ A3K57 þ6A3K56ffiffiffiffiffi
A1
p þ 12A3K55
A1
;
b96 ¼ 12C2K65 þ A2K62 �4A2K61ffiffiffiffiffi
A1
p þ 6A2K60
A1
þ A3K61
� 6A3K60ffiffiffiffiffiA1
p � 12A3K59
A1
;
b97 ¼ A1C1K56 þ 8ffiffiffiffiffiA1
pC1K55;
b98 ¼ A1C2K60 � 8ffiffiffiffiffiA1
pC2K59;
b99 ¼ 20C1K64 þ A2K57 þ6A2K56ffiffiffiffiffi
A1
p þ 12A2K55
A1
þ A3K56
þ 8A3K55ffiffiffiffiffiA1
p ;
b100 ¼ 20C2K64 þ A2K61 �6A2K60ffiffiffiffiffi
A1
p � 12A2K59
A1
þ A3K60
� 8A3K59ffiffiffiffiffiA1
p ;
Hydromagnetic Convection Flow in a Porous Medium 429
123
b101 ¼ A3K55 þ 30C1K63 þ A2K56 þ8A2K55ffiffiffiffiffi
A1
p ;
b102 ¼ A3K59 þ 30C2K63 þ A2K60 �8A2K59ffiffiffiffiffi
A1
p ;
b103 ¼20A2K64
A1
þ A1C1K59 þ30A3K63
A1
þ A1C2K55;
b104 ¼ A1C1K60 � 8ffiffiffiffiffiA1
pC1K59 þ A1C2K56 þ 8
ffiffiffiffiffiA1
pC2K55
þ 12A2K65
A1
þ 20A3K64
A1
;
b105 ¼ A1C1K61 � 6ffiffiffiffiffiA1
pC1K60 � 12C1K59 þ A1C2K57
�
þ 6ffiffiffiffiffiA1
pC2K56 þ 12C2K55 �
6A2K66
A1
þ 12A3K65
A1
�;
b106 ¼ A1C1K62 � 4ffiffiffiffiffiA1
pC1K61 þ 6C1K60 þ A1C2K58
�
þ 4ffiffiffiffiffiA1
pC2K57 þ 6C2K56 �
2A2K67
A1
� 6A3K66
A1
�;
b107 ¼ 2C1K61 � 2ffiffiffiffiffiA1
pC1K62 þ A1C1K75
�þ 2
ffiffiffiffiffiA1
pC2K58
þ2C2K57 þ A1C2K74 �2A3K67
A1
�;
b108 ¼ 2A1C1K52 þffiffiffiffiffiA1
pC1K52; b109
¼ 2A1C1K54 �ffiffiffiffiffiA1
pC2K53;
b110 ¼ A1C1K74 þffiffiffiffiffiA1
pC1K58 þ
2A2K52ffiffiffiffiffiA1
p þ A2K51
A1
;
b111 ¼ A1C2K75 �ffiffiffiffiffiA1
pC2K62 �
2A2K54ffiffiffiffiffiA1
p þ A2K53
A1
;
b112 ¼ffiffiffiffiffiA1
pC1K76 � 2A1C2K52 �
ffiffiffiffiffiA1
pC2K51 þ
A2K74ffiffiffiffiffiA1
p
þ A2K58
A1
;
b113 ¼ffiffiffiffiffiA1
pC2K76 þ 2A1C1K54 �
ffiffiffiffiffiA1
pC1K53 þ
A2K75ffiffiffiffiffiA1
p
� A2K62
A1
;
b114 ¼ A1C1K58 þ 2ffiffiffiffiffiA1
pC1K56 þ
2A2K51ffiffiffiffiffiA1
p ;
b115 ¼ A1C2K62 � 2ffiffiffiffiffiA1
pC2K61 �
2A2K53ffiffiffiffiffiA1
p ;
b116 ¼ 2A1C2K51 þ 2ffiffiffiffiffiA1
pC1K67 �
A2K58ffiffiffiffiffiA1
p � 2A2K57
A1
;
b117 ¼ 2ffiffiffiffiffiA1
pC2K67 � 2A1C1K53 þ
2A2K61
A1
� A2K62ffiffiffiffiffiA1
p ;
b118 ¼ A1C1K57 þ 3ffiffiffiffiffiA1
pC1K56;
b119 ¼ A1C2K61 � 3ffiffiffiffiffiA1
pC2K60;
b120 ¼A2K57ffiffiffiffiffi
A1
p þ 3A2K56
A1
� 3K66
ffiffiffiffiffiA1
pC1;
b121 ¼3A2K60
A1
� A2K61ffiffiffiffiffiA1
p þ 3ffiffiffiffiffiA1
pC2K66;
b122 ¼ A1C1K56 þ 4ffiffiffiffiffiA1
pC1K55; b123
¼ A1C2K60 � 4ffiffiffiffiffiA1
pC2K59;
b124 ¼ 4ffiffiffiffiffiA1
pC1K65 þ
A2K56ffiffiffiffiffiA1
p þ 4A2K55
A1
;
b125 ¼ 4ffiffiffiffiffiA1
pC2K65 þ
A2K60ffiffiffiffiffiA1
p � 4A2K59
A1
;
b126 ¼ 5ffiffiffiffiffiA1
pC1K64 þ
A2K55ffiffiffiffiffiA1
p ;
b127 ¼ 5ffiffiffiffiffiA1
pC2K64 þ
A2K59ffiffiffiffiffiA1
p ;
b128 ¼5A2K64
A1
� A1C1K59 � A1C2K55;
b129 ¼ 4ffiffiffiffiffiA1
pC1K59 � A1C1K60 � A1C2K56 � 4
ffiffiffiffiffiA1
pC2K55
þ 4A2K65
A1
;
b130 ¼ 3ffiffiffiffiffiA1
pC1K60 � A1C1K61 � A1C2K57 � 3
ffiffiffiffiffiA1
pC2K56
� 3A2K66
A1
;
b131 ¼ 2ffiffiffiffiffiA1
pC1K61 � A1C1K62 � A1C2K58 � 2
ffiffiffiffiffiA1
pC2K57
� 2A2K67
A1
;
b132 ¼ffiffiffiffiffiA1
pC1K62 � A1C1K75 �
ffiffiffiffiffiA1
pC2K58 � A1C2K74
þ A2K74
A1
;
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