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					    INTERNATIONAL JOURNAL OF ADVANCED RESEARCH ISSN
International Journal of Advanced Research in Engineering and Technology (IJARET),IN
0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 5, July – August (2013), © IAEME
               ENGINEERING AND TECHNOLOGY (IJARET)
ISSN 0976 - 6480 (Print)
ISSN 0976 - 6499 (Online)
                                                                            IJARET
Volume 4, Issue 5, July – August 2013, pp. 231-242
© IAEME: www.iaeme.com/ijaret.asp
Journal Impact Factor (2013): 5.8376 (Calculated by GISI)
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      MHD FLOW AND HEAT TRANSFER FOR THE UPPER CONVECTED
      MAXWELL FLUID OVER A STRETCHING SHEET WITH VISCOUS
                         DISSIPATION

    Anand H. Agadi1*, M. Subhas Abel2, Jagadish V. Tawade3 and Ishwar Maharudrappa4
     1*
       Department of Mathematics, Basaveshwar Engineering College, Bagalkot-587102, INDIA
            2
              Department of Mathematics, Gulbarga University, Gulbarga- 585 106, INDIA
     3
       Department of Mathematics, Bheemanna Khandre Institute of Technology, Bhalki-585328
         4
           Department of Mathematics, Basaveshwar Engineering College, Bagalkot-587102


ABSTRACT

        In the present work, the effect of MHD flow and heat transfer within a boundary layer flow
on an upper-convected Maxwell (UCM) fluid over a stretching sheet is examined. The governing
boundary layer equations of motion and heat transfer are non-dimensionalized using suitable
similarity variables and the resulting transformed ordinary differential equations are then solved
numerically by shooting technique. For a UCM fluid, a thinning of the boundary layer and a drop in
wall skin friction coefficient is predicted to occur for higher the elastic number which agrees with the
results of Hayat et al. The objective of the present work is to investigate the effect of various
parameters like elastic parameter β , magnetic parameter Mn, Prandtl number Pr and Eckert number
Ec on the temperature field above the sheet.

Key words: Eckert number, Elastic Parameter, Magnetic parameter, UCM fluid.

1. INTRODUCTION

        The studies of boundary layer flows of Newtonian and non-Newtonian fluids over a
stretching surface have received much attention because of their extensive applications in the field of
metallurgy and chemical engineering particularly in the extrusion of polymer sheet from a die or in
the drawing of plastic films. During the manufacture of these sheets, the melt issues from a slit and is
subsequently stretched to achieve the desired thickness.                   Such investigations of
magnetohydrodynamics (MHD) flow are very important industrially and have applications in
different areas of research such as petroleum production and metallurgical processes. The magnetic
field has been used in the process of purification of molten metals from non-metallic inclusions. The
study of flow and heat transfer caused by a stretching surface is of great importance in many

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International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN
0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 5, July – August (2013), © IAEME

manufacturing processes such as in extrusion process, glass blowing, hot rolling, and manufacturing
of plastic and rubber sheets, crystal growing, continuous cooling and fibers spinning. In all these
cases, a study of flow field and heat transfer can be of significant importance because the quality of
the final product depends to a large extent on the skin friction coefficient and the surface heat
transfer rate (Fox.V.G.,Ericksen [11], Siddappa and Abel [12]). Sarpakaya [1] was the first
researcher to study the MHD flow of a non-Newtonian fluid. Prandtl’s boundary layer theory proved
to be of great use in Newtonian fluids as Navier-Stokes equations can be converted into much
simplified boundary layer equation which is easier to handle. Crane [2] was the first among others to
consider the steady two-dimensional flow of a Newtonian fluid driven by a stretching elastic flat
sheet. Further many authors (Refs. Grubka et.al [3], Dutta et.al [4], Jeng et.al [5], Chakrabarti et.al
[6] and Abel et.al [7]) have extended the Cranes work.




                       Fig.1. Schematic showing flow above a stretching sheet

        Generally it is observed that rheological properties of a material are specified by their
constitutive equations. The simplest constitute equation for a fluid is a Newtonian one and the
governing equation for such a fluid is the Navier-Stokes equation. But in many fields, such as food
industry, drilling operations and bio-engineering, the fluids, rather synthetic or natural or mixtures of
different stuffs such as water, particles, oils, red cells and other long chain of molecules. This
combination imparts strong non-Newtonian characteristics to the resulting liquids. In these cases, the
fluids have been treated as non-Newtonian fluids. To have a better control on the rate of cooling, in
recent years it has been proposed that it might be advantageous for water to be made more or less
viscoelastic, say, through the use of polymeric additives (Andersson [9]). Recently, Liu [21] have
investigated heat and mass transfer for a hydromagnetic flow over a stretching sheet.
        Although there is no doubt about the importance of the theoretical studies cited above, but
they are not above reproach. For example, the viscoelastic fluid models used in these works are
simple models such as second-order model and/or Watler’s B model which are known to be good
only for weakly elastic fluids subject to slow and/or slowly-varying flows (Bird et al [10]). A non-
Newtonian second grade fluid does not give meaningful results for highly elastic fluids (polymer
melts) which occur at high Deborah numbers [18-19]. Therefore, the significance of the results

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reported in the above works are limited, at least as far as polymer industry is concerned. Obviously,
for the theoretical results to become of any industrial significance, more realistic viscoelastic fluid
models such as upper-convected Maxwell model or Oldroyd-B model should be invoked in the
analysis. Indeed, these two fluid models have recently been used to study the flow of viscoelastic
fluids above stretching and non-stretching sheets but wadehith no heat transfer effects involved
(Pahlavan et al[14] and Renardy[15]). Some researchers, Pahlavan et al[14], Renardy[15], Aliakbar
et al[18], Rajgopal [20] have done the work related to UCM fluid by using HAM- method and the
researcher Conte et al [19] have studied UCM fluid by using numerical methods with no heat
transfer.
        The focal point in the present work is to investigate MHD flow and heat transfer for the
Upper Convected Maxwell fluid over a stretching sheet with viscous dissipation. To achieve this
goal, use will be made of a recent analysis carried out by Hayat et al. [13] in which the velocity field
above the sheet was calculated for MHD flow of an UCM fluid with no heat transfer involved using
homotopy analysis method (HAM). To the best of our knowledge, no numerical solution has
previously been investigated for MHD flow and heat transfer of a UCM fluid above a stretching
sheet. Such investigation has important applications in polymer industry. Also the boundary layer
flow over a stretching surface is often encountered in many engineering disciplines.

2. GOVERNING EQUATIONS AND BOUNDARY CONDITIONS

       The equations governing the heat transfer and momentum between a stretching sheet and the
surrounding fluid (see fig.1) can be significantly simplified if it can be assumed that boundary layer
approximations are applicable to both momentum and energy equations. Although this theory is
incomplete for Viscoelastic fluids, but has been recently discussed by Renardy [15], it is more
plausible for Maxwell fluids as compared to other viscoelastic fluid models. For MHD flow of an
incompressible Maxwell fluid resting above a stretching sheet, the equations governing transport of
heat and momentum can be written as Sadegy et al [16] and Pahlavan et al[17].

            ∂u ∂v
              +   = 0,                                                                  (1)
            ∂x ∂y

            ∂u    ∂u   ∂ 2u    ∂ 2u      ∂ 2u     ∂ 2 u  σB02
               +v    =υ 2 − λ u 2 2 + v 2 2 + 2uv       −     u                        (2)
            ∂x    ∂y   ∂y      ∂x        ∂y       ∂x∂y    ρ

        where B 0 , is the strength of the magnetic field, υ is the kinematic viscosity, µ is dynamic
viscosity of the fluid and λ is the relaxation time Parameter of the fluid. As to the boundary
conditions, we are going to assume that the sheet is being stretched linearly. Therefore the
appropriate boundary conditions on the flow are

            u = Bx,    v = 0 at y = 0,
            u→0       as   y→∞                                                          (3)

        where B>0, is the stretching rate. Here x and y are, respectively, the directions along and
perpendicular to the sheet, u and v are the velocity components along x and y directions. The flow is
caused solely by the stretching of the sheet, the free stream velocity being zero. Eqs. (1) and (2)
admit a selt-similar solution of the form


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                                                                         1
                                                                B 2
             u = Bxf ′(η ), v = ν B f (η ),                η =   y,                               (4)
                                                               ν 

where superscript ' denotes the differentiation with respect to η . Clearly u and v satisfy Eq. (1)
identically. Substituting these new variables in Eq. (2), we have

                                      2
              f ′′′ − M 2 f ′ − ( f ′ ) + f ′′ + β ( 2 ff ′ ′′ − ff ′′′ ) = 0,
                                                          f                                         (5)

  Here M and β are magnetic and elastic parameters.
 The boundary conditions (3) become

             f ′ ( 0 ) = 1,        f (0 ) = 0             at        η = 0
             f ′( ∞ ) → 0 ,       f ′′ ( 0 ) → 0          as        η → ∞                           (6)


3. HEAT TRANSFER ANALYSIS

      By using usual boundary layer approximations, the equation of the energy for two-
dimensional flow is given by

                                                               2
             ∂T    ∂T   k ∂ 2T      µ                  ∂u 
           u    +v    =        2
                                 +                      .                                           (7)
             ∂x    ∂y ρ C p ∂y     ρC p                ∂y 

         where T , ρ , c p and k are, respectively, the temperature, the density, specific heat at
constant pressure and the thermal conductivity is assumed to vary linearly with temperature. We
define the dimensionless temperature as

                                                                    2
                    T − T∞                             x
           θ (η ) =         ,       where Tw − T∞ = b   θ (η )                      ( PST Case)
                    Tw − T∞                           l                                           (8a)


                                                                             2
                        T - T∞              D  x                               υ
          g(η) =      2
                           , where Tw − T∞ =                                       (PHF Case)
                   x 1 ν                  k l                                b                   (8b)
                 b 
                  l k b

       The thermal boundary conditions depend upon the type of the heating process being
considered. Here, we are considering two general cases of heating namely, (i) Prescribed surface
temperature and (ii) prescribed wall heat flux, varying with the distance.

3.1. Governing equation for the prescribed surface temperature case (PST - Case)
        For this heating process, the prescribed temperature is assumed to be a quadratic function of x
is given by



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International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN
0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 5, July – August (2013), © IAEME
                                              2
                                      x
u = Bx, v = 0, T = Tw ( x) = T0 − Ts            at y = 0.
                                     l                                                      (9)
 u = 0,   T → T∞       as y → ∞
Where l is the characteristic length. Using (4), (5) and (9), the dimensionless temperature variable θ
given by (8a), satisfies

Pr  2 f ′θ − θ ′ f − Ecf ′′2  = θ ′′,
                                                                                            (10)
                 µcp                                                 2 2
                                                                    bl
Where Pr =              is the Prandtl number and Ec =                  is the Eckert number. The corresponding
             k                                                      ACp
boundary conditions are

θ (0) = 1 at η = 0
θ (∞) = 0 as η → ∞                                                                            (11)

3.2. Governing equation for the prescribed heat flux case (PHF - Case)
       The power law heat flux on the wall surface is considered to be a quadratic power of x in the
form

                                          2
              ∂T             x
u = Bx, − k       = qw = D       at y = 0
              ∂y  w          l                                                 (12)
u → 0, T → T∞ as y → ∞.
Here D is constant, k is thermal conductivity. Using (4), (5) and (12), the dimensionless temperature
variable g given by (8b), satisfies

          Pr  2 f ′ g − g ′ f − Ecf ′′2  = g ′′,
                                                                                            (13)

The corresponding boundary conditions are g ′ (η ) = −1, g (∞) = 0.         (14)
       The rate of heat transfer between the surface and the fluid conventionally expressed in
dimensionless form as a local Nusselt number and is given by

              x         ∂T 
Nu x ≡ −                    = − x Re θ '(0)                                                 (15)
           Tw − T∞      ∂y  y =0

Similarly, momentum equation is simplified and exact analytic solutions can be derived for the skin-
friction coefficient or frictional drag coefficient as

      ∂u 
     µ 
      dy  y =0             1                                                                (16)
Cf ≡          2
                 = − f ′′(0)
      ρ ( Bx)                Re x
                 ρ Bx 2
where Re x =            is known as local Reynolds number
                   µ


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4. NUMERICAL SOLUTION

        We adopt the most effective shooting method (see Refs.. Conte et al [19]) with fourth order
Runge-Kutta integration scheme to solve boundary value problems in PST and PHF cases mentioned
in the previous section. The non-linear equations (5) and (10) in the PST case are transformed into a
system of five first order differential equations as follows:

           df 0
                = f1 ,
           dη
           df1
                = f2 ,
           dη
                          2
           df 2 ( f1 ) + M f1 − f 0 f 2 − 2 β f 0 f1 f 2
                          2

               =                                         ,                               (17)
           dη               1 − β f02
           dθ 0
                = θ1 ,
           dη
           dθ1
                = Pr  2 f1θ 0 − θ1 f 0 − Ecf ′′2  .
                                                 
           dη

Subsequently the boundary conditions in (6) and (11) take the form,

           f 0 (0) = 0,       f1 (0) = 1,   f1 (∞) = 0,
                                                                                         (18)
           f 2 (0) = 0,       θ 0 (0) = 0, θ 0 (∞) = 0.

        Here f 0 = f (η ) a n d θ 0 = θ (η ) . aforementioned boundary value problem is first
converted into an initial value problem by appropriately guessing the missing slopes f 2 (0) and θ1 (0) .
The resulting IVP is solved by shooting method for a set of parameters appearing in the governing
equations with a known value of f 2 (0) and θ1 (0) . Once the convergence is achieved we integrate the
resultant ordinary differential equations using standard fourth order Runge–Kutta method with the
given set of parameters to obtain the required solution.

5. RESULTS AND DISCUSSION

        The exact solution do not seem feasible for a complete set of equations (5)-(10) because of
the non linear form of the momentum and thermal boundary layer equations. This fact forces one to
obtain the solution of the problem numerically. The effect of several parameters controlling the
velocity and temperature profiles obtained are compared with Hayat et.al[13], shown graphically and
discussed briefly.




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      1.0                                                                                      1.0
                                                                 B=0                                                                                       B=0

      0.8                                                                                      0.8



      0.6                                                                                      0.6

                                                                                         f(η)
  f'(η)
      0.4                                                                                      0.4
                            M=0,1,2,3,4,5

                                                                                                                 M=0,1,2,3,4,5
      0.2                                                                                      0.2




      0.0                                                                                      0.0


            0       1             2          3       4       5         6                             0       1           2           3       4       5             6
                                                                                                                                     η
                                             η
      Fig.2(a). The effect of MHD parameter Mon u-velocity component f ' at β =0               Fig.2(b). The effect of MHD parameter M on v-velocity component f' at β =0




        Figs.2(a) and 2(b) shows the effect of magnetic parameter M, in the absence of Elastic
parameter (at β = 0) on the velocity profile above the sheet. An increase in the magnetic parameter
leads in decrease of both u- and v- velocity components at any given point above the sheet. This is
due to the fact that applied transverse magnetic field produces a drag in the form of Lorentz force
thereby decreasing the magnitude of velocity. The drop in horizontal velocity as a consequence of
increase in the strength of magnetic field is observed.


          1.0                                                                            1.0
                                                                       B=1                                                                               B=1

          0.8                                                                            0.8




          0.6                                                                            0.6

                                                                                     f(η)
  f'(η)
          0.4                                                                            0.4
                             M=0,1,2,3,4,5

                                                                                                                 M=0,1,2,3,4,5
                                                                                         0.2
          0.2



                                                                                         0.0
          0.0

                                                                                               0         1           2           3       4       5             6
                0       1             2          3       4       5           6                                                   η
                                                 η
                                                                                         Fig.3(b). The effect of MHD parameter M on v-velocity component f' at β =1
      Fig.3(a). The effect of MHD parameter M on u-velocity component f' at β




       Figs.3(a) and 3(b) show the same effect as said above, but, in the presence of Elastic
parameter (at β = 1) . That is, an increase in the magnetic parameter leads in increase of fluid
temperature at any given point above the sheet.


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         1.0                                                                                            1.0
                                                                                                                                                                    β =0.0
                                                                          M=0                                     M=0
                                                                                                                                                                    β =0.1

                                                                                                        0.8
         0.8                                                                                                                                                        β =0.5

                                                                                                                                                                    β =1.0
                                                                                                        0.6
         0.6
                                                                                                   f(η)                                                             β =2.0
   f'(η)
                                                                                                        0.4
         0.4
                                                                                                                                                                    β =5.0
                              β = 0,0.1,0.5,1,2,5
                                                                                                        0.2
         0.2


                                                                                                        0.0
         0.0
                                                                                                              0         1       2       3       4       5       6          7
                                                                                                                                            η
               0       1           2       3        4       5        6          7
                                                η
  Fig.4(a). The effect of Elastic parameter β on u-velocity component f ' at M =0                  Fig.4(b). The effect of E            eter
                                                                                                                            lastic param β on v-velocity component f ' at M=0




       Figs.4(a)and 4(b) show the effect of Elastic parameter β , in the absence of magnetic number
(at M = 0) on the velocity profile above the sheet. An increase in the Elastic parameter is noticed to
decrease both u- and v- velocity components at any given point above the sheet.

     1.0                                                                                     1.0
                                                                    M=1                                                                                         M=1

     0.8                                                                                     0.8



     0.6                                                                                     0.6

  f(η)                                                                                    f '(η)
     0.4                                                                                     0.4

                           β =0,0.1,0.5,1,2,5
     0.2
                                                                                                                        β=0,0.1,0.5,1,2,5
                                                                                             0.2



     0.0
                                                                                             0.0

           0       1           2       3        4       5       6         7
                                           η                                                        0             1         2       3       4       5       6          7
                                                                                                                                        η
                                       eter
  Fig.5(a). The effect of Elastic param β on u-velocity component f at M=1                Fig.5(b). Theeffect of E           eter
                                                                                                                  lasticparam β onv-velocitycomponent f' at M=1




       Figs.5(a)and 5(b) show the effect of Elastic parameter β , in the presence of magnetic number
(at M = 1) on the velocity profile above the sheet. An increase in the Elastic parameter is noticed to
decrease both u- and v- velocity components at any given point above the sheet.


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              1.0                                                                                       1.0
                                                                                                                                                                      PFH
                                                                        PTS
                                                                                                                                                                       = .0
                                                                                                                                                                      B1
                                                                         = .0
                                                                        B1
                                                                                                        0.8                                                            r= .0
                                                                                                                                                                      P1
              0.8                                                        = .0
                                                                        M1
                                                                         r= .0
                                                                        P1

                                                                                                        0.6
              0.6
                                                                                                θ(η)
          θ(η)
                                                                                                                               M=0,1,2,3,4,5
                                 M=0,1,2,3,4,5                                                          0.4
              0.4


                                                                                                        0.2
              0.2


                                                                                                        0.0
              0.0

                                                                                                              0                2               4            6               8
                                                                                                                                               η
                    0           2              4               6                  8
                                               η
                                                                                                                     he          H aram
                                                                                                          Fig.6(b). T effect of M Dp eter Montemperatureprofilesθ(η)
                 F          he          H      eter
                  ig.6(a). T effect of M Dparam Montemperatureprofilesθ(η)




        Figs.6(a)and 6(b) show the effect of magnetic parameter on the temperature profiles above
the sheet for both PST and PHF cases. An increase in the magnetic parameter is seen to increase the
fluid temperature above the sheet. That is, the thermal boundary layer becomes thicker for larger the
magnetic parameter.

                                                                                                7

                                                                            PST                                                                                       PHF
              1.0
                                                                                                6

                                                                        Ec=1.0
              0.8                                                                               5


                                                                                                4                                  Pr = 0.01
              0.6
                                                Pr = (0.01, 0.1, 1, 5, 10)
     θ (η )




                                                                                       g (η )
                                                                                                3

              0.4                                                                                                            Pr = 0.1
                                                                                                2

              0.2
                                                                                                1                 Pr = 1.0


              0.0                                                                               0
                    0    1      2       3       4       5      6        7         8                 0             1      2         3       4       5    6         7         8

                                               η                                                                                          η
                        Fig 7(a): Effect of Pr on temperature profile                                             Fig 7(b): Effect of Pr on tempreture gradiant




        Figs. 7(a) and 7(b) show the effect of Prandtl number on the temperature profiles above the
sheet for both PST and PHF cases. An increase in the Prandtl number is seen to decrease the fluid
temperature θ (η ) above the sheet. That is not surprising realizing the fact that the thermal boundary
becomes thinner for, larger the Prandtl number. Therefore, with an increase in the Prandtl number the
rate of thermal diffusion drops. This scenario is valid for both PST and PHF cases. For the PST case
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International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN
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the dimensionless wall temperature is unity for all parameter values. However, it may be other than
unity for the PHF case because of its differing thermal boundary conditions.


             1.0                                                                                  7
                                                                         PST                                                                                 PHF
                                                                                                  6
             0.8

                                                                                                  5

             0.6
                                                                                                  4                           Ec = 0.01, 1.0, 5.0, 10
     θ (η)




                                                                                         θ (η )
                                                                                                  3
             0.4                Ec = 0,1, 0,5, 1.0

                                                                                                  2

             0.2
                                                                                                  1


             0.0                                                                                  0
                   0   1        2        3           4     5         6         7                      0    1      2       3      4       5       6       7         8
                                          η                                                                                        η
                       Fig.8(a):Effect of Ec on tempreture profile                                        Fig.8(b):Effect of Ec on tempreture gradiant




        Figs. 8(a) and 8(b) show the effect of Eckert number on the temperature profiles above the
sheet for both PST and PHF cases. An increase in the Eckert number is seen to enhance the
temperature in the fluid, i.e. increasing values of Ec contributes in thickening of thermal boundary
layer for effective cooling of the sheet, a fluid of low viscosity is preferable.
        A drop in skin friction as investigated in this paper has an important implication that in free
coating operations, elastic properties of the coating formulations may be beneficial for the whole
process. Which means that less force may be needed to pull a moving sheet at a given withdrawal
velocity or equivalently higher withdrawal speeds can be achieved for a given driving force resulting
in, increase in the rate of production (Rajgopal [20] ). A drop in skin friction with increase in Elastic
parameter as observed in Table 1 gives the comparison of present results with that of Hayat et al
[13], without any doubt, from this table, we can claim that our results are in excellent agreement with
that of Hayat et al. [13].

6. CONCLUSION

        The present work analyses, the MHD flow and heat transfer within a boundary layer of UCM
fluid above a stretching sheet. Numerical results are presented to illustrate the details of the flow and
heat transfer characteristics and their dependence on the various parameters.
We observe that, when the magnetic parameter increases the velocity decreases, also, for increase in
Elastic parameter, there is decreases in velocity. The effect of magnetic field and Elastic parameter
on the UCM fluid above the stretching sheet is to suppress the velocity field, which in turn causes the
enhancement of the temperature.
        Also it is observed that, an increase of Prandtl number and Eckert number results in
decreasing thermal boundary layer thickness and more uniform temperature distribution across the
boundary layer in both the PST and PHF cases.




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         TABLE 1: Comparison of values of skin friction coefficient f ′′ ( 0 ) with Mn = 0.0

                                      Sl No.          Author      Remark
                                          11         6.699120    1.307785
                                          22         3.742330    1.195155
                                          33         2.680940    1.245795
                                          44        1.972380     1.277762
                                          55        1.442631     1.279177
                                          66        1.012784     1.233549



       TABLE 2: Comparison values of skin friction coefficient f ′′ ( 0 ) with M= 0 and M= 0.2
                       Hayat et. al [13]                         Present Results
         S
                     M=0.0                M=0.2                    M=0.0               M=0.2
        0.0         -1.90250             -1.94211                -0.999962           -1.095445
        0.4         -2.19206             -2.23023                -1.101850           -1.188270
        0.8         -2.50598             -2.55180                -1.196692           -1.275878
        1.2         -2.89841             -2.96086                -1.285257           -1.358733
        1.6         -3.42262             -3.51050                -1.368641           -1.437369
        2.0         -4.13099             -4.25324                -1.447617           -1.512280



       TABLE 3: Comparison values of −θ ′ ( 0 ) and g ( 0 ) for various values of β , Mn, Pr and Ec
              β       M             Pr               Ec            − θ ′(0)         g ( 0)
               0      1.0           1.0              1.0           1.414214        0.805288
               1      1.0           1.0              1.0           1.588881        0.849757
               2      1.0           1.0              1.0           1.750296        0.893245
               1       0            1.0              1.0           1.241599        0.795812
              1.0      1            1.0              1.0           1.588881        0.850611
              1.0      2            1.0              1.0           1.875434        0.900462
              1.0     1.0          0.01              1.0           0.146901        6.464132
              1.0     1.0           0.1              1.0           0.182179        4.001766
              1.0     1.0            1               1.0           0.422942        1.489778
              1.0     1.0           1.0             0.02           1.163098        0.861570
              1.0     1.0           1.0              1.0           0.422942        1.489778
              1.0     1.0           1.0              2.0           0.332320        2.130806


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