ENTROPY GENERATION ANALYSIS FOR SECOND ORDER …raops.org.in/epapers/dec19_4.pdfexplicitly presented...
Transcript of ENTROPY GENERATION ANALYSIS FOR SECOND ORDER …raops.org.in/epapers/dec19_4.pdfexplicitly presented...
-
Journal of Rajasthan Academy of Physical Sciences
ISSN : 0972-6306; URL : http://raops.org.in
Vol.18, No.3&4, July-December, 2019, 155-168
ENTROPY GENERATION ANALYSIS FOR SECOND ORDER
FLUID FLOW OVER A NON ISOTHERMAL STRETCHING
SURFACE
Paresh Vyas
1 and Kusum Yadav
2
Department of Mathematics, University of Rajasthan, Jaipur, 302004, India
E-mail: [email protected],
Abstract: The paper presents entropy analysis for radiative dissipative second order fluid
flow over a stretching sheet subjected to power-law temperature in a saturated porous
medium. Similarity transformations are used to convert the governing partial differential
equations to ordinary differential equations (ODE). The BVP is solved numerically to get
the velocity distribution, temperature distribution and entropy generation. The quantities
of interest are portrayed graphically and discussed.
Keywords: Entropy, stretching sheet, porous, second order fluid, Radiation, Dissipation
1. Introduction
Entropy generation analysis for non Newtonian fluid flow over a stretching sheet is
peculiarly interesting owing its vast applications in biological sciences, geophysics &
mining industries and chemical & plastic processing industries. For long, Non-Newtonian
behaviour has been treated for heat transfer aspects only due to industrial applications.
Recently it has been realised that an entropy generation analysis would be more insight
giving in designing optimal device and to understand the phenomenon.
There has been long history of studies in Boundary layer flow on a moving continuous
solid surfaces pioneered first by Sakiadis [28, 29] and later on experimentally verified by
Tsou et al. [31]. Gupta and Gupta [12] investigated heat transfer from an isothermal
stretching sheet subject to suction or blowing. The case of exponentially stretching sheet
in viscous fluid was studied by Crane [10]. All these studies were restricted to Newtonian
fluids. Bujurke et al. [6] studied the flow and heat transfer of second order fluid over
stretching sheet. Vajravelu and Rollins [32] devised an analytical solution for heat
transfer characteristics in viscoelastic second order fluid over a stretching sheet taking
frictional heating and internal heat generation into account. Akkayya and Talla [2]
explicitly presented the analysis of boundary layer flow and heat transfer of visco–elastic
fluid through porous medium over an exponentially stretching sheet with non-uniform
heat source employing Homotopy Analysis Method (HAM). Nataraja et al. [22] obtained
the closed-form solutions for the flow of a second-order fluid over a stretching surface
having power-law temperature. Pillai et al. [24] studied heat transfer in a visco-elastic
http://raops.org.in/mailto:[email protected]:[email protected]
-
156 Paresh Vyas and Kusum Yadav
boundary layer flow through a porous medium. Heydari and Taleghani [14] analysed
boundary layer in MHD flow of non-Newtonian visco- elastic fluid on stretching sheet.
The flow of a power-law fluid due to a linearly stretching sheet and heat transfer
characteristics using variable thermal conductivity in the presence of a non-uniform heat
source/sink was studied by Abel et al. [1]. Zaib et al. [40] obtained Dual similarity
solutions for velocity and temperature of a non-Newtonian Casson fluid and heat transfer
due to an exponentially permeable shrinking sheet with viscous dissipation. Khan and
Rahman [17] investigated flow and heat transfer of a modified second order fluid over
non-linearly stretching sheet. Vijaya Laxmi and Shankar [33] proposed radiative
boundary layer flow and heat transfer of Nanofluid over a nonlinear stretching sheet with
slip conditions and suction. Imtiaz et al. [16] explored the flow of Jeffrey fluid due to a
curved stretching sheet.
Second law of thermodynamics is a pertinent tool to address inherent thermodynamic
irreversibility. It underscores the processes that involves transfer or conversion of energy
are irreversible. Bejan [3-5] in his innovative works shown that entropy generation
minimization can be actualised by selecting parameters’ vlues that have bearing on
entropy generation. In thermofluidic configurations entropy production is caused by heat
transfer, fluid friction, imposed magnetic field, and radiative heat transfer.
There has been a great surge of studies in entropy generation aspects in fluid flow
systems. These investigations were carried first primarily in idealized flow
configurations. The second law characteristics of heat transfer and fluid flow for forced
convection inside channel with circular cross-section and channel made of two parallel
plates was analyzed by Mahmud and Fraser [20]. Chauhan and Olkha [7] examined
entropy generation on non-Newtonian fluid flow in annular pipe with naturally permeable
boundaries. Chauhan and Rastogi [8] studied entropy generation in flow through a porous
medium over a stretching sheet in the presence of a magnetic field. Srivastava et al.[30]
analysed entropy generation analysis for oscillatory flow in vertical channel filled with
porous medium. Vyas and his coworkers [34,35,36,37,38.39] examined entropy
generation in variety of flow configurations. Makinde and Aziz [21] performed analytical
and numerical analysis of the second law of thermodynamics for plane Poiseuille flow
with asymmetric convective heat transfer taking variable fluid viscosity. M.H.Yazdi et al.
[19] presented the first and second law analysis of power-law non-Newtonian flow over
embedded open parallel micro channels within micro patterned permeable continuous
moving surface are examined at prescribed surface temperature. Chauhan and kumar [9]
studied heat transfer and entropy generation for compressible fluid flow in a channel
partially filled with a porous medium. Hooshmand et al. [15] numerically investigated the
effects of magnetic field strength, thermal radiation, Joule heating, and viscous heating
on a forced convective flow of a non-Newtonian, incompressible power law fluid in an
axisymmetric stretching sheet with variable temperature wall. Rashidi et al.[25,26]
studied the analysis of entropy generation for Stagnation point flow in a porous medium
over a permeable stretching surface and Rashidi et al. [26] also investigated entropy
generation in an MHD flow over a rotating porous disk with variable physical properties.
-
Entropy Generation Analysis for... 157
Rashidi et al. [27] also studied convective flow of a third grade non-Newtonian fluid due
to a linearly stretching sheet subject to a magnetic field.
Dehsara et al. [11] discussed entropy analysis for MHD flow over a non-linear inclined
transparent plate in a porous medium taking solar radiation into account. Lin and Chen
[18] analysed irreversibility of heat transfer for a Non-Newtonian power-law flow with
power-law temperature. They exploited differential transform method (DTM) with
shooting method to solve the non-Newtonian power-law flow problem. Habibi Matin et
al. [13] studied numerically entropy analysis in mixed convection MHD flow of
nanofluid over a non-linear stretching sheet taking viscous dissipation and variable
magnetic field into account using the Keller-Box scheme. Noghrehabadi et al. [23]
presented entropy analysis for Nano fluid flow over a stretching sheet in the presence of
heat generation/ absorption and partial slip.
The central objective of this paper is to analyse the entropy generation in second order
fluid over a stretching sheet embedded in a porous medium. The governing equations are
solved numerically using Runge Kutta method along with shooting technique. The results
obtained for the pertinent parameters are depicted graphically.
2. Mathematical Formulation
We consider a 2-D boundary layer flow of a viscous, incompressible, electrically
conducting second order fluid past a stretching sheet placed at the bottom of the porous
medium. A Cartesian coordinate system is chosen wherein the x-axis is along the sheet
and the y-axis is taken normal to it. Two equal and opposite forces are applied along the
sheet so that the position of the origin is unaltered. The stretching velocity varies linearly
with the distance from the origin. A magnetic field of uniform strength B is applied along
y-axis. Further, it is assumed that both the fluid and the porous medium are in thermal
equilibrium. The Rooseland approximation is followed to describe the heat flux in the
energy equation. The governing equation and the associated boundary condition for the
set up are as follows:
u v0
x y
(1)
2 2 2 3 2
2 2 2 3
o
u u d u u u v u νu σB uu v ν k u v
x y y x y y y y K ρ
(2)
2 22 2r
p 2
o
T T T q µuρC u v κ σB u
x x y y K
(3)
and the associated boundary conditions are
-
158 Paresh Vyas and Kusum Yadav
Tβ
w w
xy=0: u u =cx,v 0, T
L=T T
(4)
u 0, T Ty : (5)
where (u, v) are the velocity components along (x, y) directions respectively, uw is the
stretching velocity, c > 0 is a given stretching parameter, T is the temperature, Tw is the
surface temperature, T∞ is a uniform temperature of the ambient fluid, Ko is the
permeability of the porous medium, σ is the electrical conductivity, ρ is the density, ν =
µ/ρ is the kinematic viscosity, A is constant, L is the characteristic length, βT is a
constant, κ is the thermal conductivity, B is the applied magnetic field, k is a positive
parameter associated with viscoelastic fluid, Cp is the specific heat at constant pressure.
The radiative heat flux qr is described as follows
4
r
4β Tq
3δ y
(6)
where β and δ are the Stephen-Boltzmann constant and the mean absorption coefficient
respectively. Temperature difference within the flow is assumed to be sufficiently small
so that we can express T4 as a linear function of temperature T, using a truncated Taylor
series about the free stream temperature T∞ to yield
4 3 4T 4T T 3T (7)
3. Solution
Introducing the stream function ѱ such that
u , vy x
0 w
x T Tf ( ),
u L T TRe
where 0 1xx y kc
, y ,u cL,k , Re yL L L
.
The equations (1)-(5) are transformed to
2 2 211 1
ff f k 2f f f ff M fR K
fe
(8)
2 2 2Br 1
1 N θ Prfθ M f x 0Re K
(9)
-
Entropy Generation Analysis for... 159
subject to the boundary conditions
0: f 0, f 1, 1
(10)
: f 0, 0
(11)
Here prime denotes differentiation with respect to η and Re, Pr, K, M. Br and N are the
Reynolds number, Prandtl number, permeability parameter, Magnetic field parameter,
Brinkman number and radiation parameter respectively defined as Re = uoL /ν, 2 32
2 0 0P
w 0
K c uC 16 TBPr ,M ,K ,Br , N
c (T T ) 3
,.
The equation (8) subject to boundary conditions given in equation (11) admits the
solution of the form
1
1
m1 1f (1 e ), m , 0 k 1m 1 k
The energy equation (9) is obtained in the following form
2 2 2Br 1(1 N) Prf M x f 0Re K
(12)
Constrained by the end conditions are 0 1, 0
(13)
3.1 Solution Technique:
The non dimensional boundary value problem (BVP) described by (12)-(13) has been solved
by Runge-Kutta integration scheme together with shooting technique. In order to employ
shooting method, the BVP is converted first to a system of initial value problems. In the
present case, the BVP is reduced to following system of initial value problems (IVP):
f p (14)
q (15)
2 2 21 Br 1q Prf M x f
1 N Re K
(16)
Together with initial conditions
0f (0) 1, q(0) a (17)
The above system of initial value problems is solved in the solution space with a proper
guess value a0 (say) for the unknown quantity 0 such that the end condition θ (1) = 0 is satisfied. If the end condition is not satisfied for this guess value then the system of
-
160 Paresh Vyas and Kusum Yadav
IVP’s is solved with another guess value a1. If the end conditions still not satisfied with
suitable error tolerance, then new refined guess value is generated using secant method.
The process continues until the end condition is satisfied to the prescribed accuracy. In
order to have confidence in numerical code of the problem in hand, a step size of
∆η=0.001 was found to be satisfactory for prescribed error tolerance of magnitude10-7
after a rigourous grid independence exercise.
4. Second Law Analysis
The local volumetric rate of entropy generation SG for the present problem is given as follows
2 22 2 2 2
G 2
0
k T 16 T B u u uS
T x 3 y T T K T y
(18)
In order to define the dimensionless entropy generation rate we prescribe the
characteristic entropy generation rate SG0 and the entropy generation number Ns
respectively as follows
2
w GG0 s2 2
G0
Re(T T ) SS and N
T L S
(19)
Consequently the entropy generation number Ns is found to be
2 2 2 2 2
s 1 2
Br 1N (1 N) M x f Br x N N
Re K
(20)
where
2 2 2 2 2
1 2
Br 1N (1 N) , N M x f Br x
Re K
(21)
Obviously the terms N1 and N2 stand for heat transfer irreversibility and dissipative
irreversibility respectively.
The Bejan Number Be is defined as follows
1
1 2
HTI NBe
HTI FFI N N
(22)
5. Results and Discussions
In order to have the plots for entropy generation number Ns we require the distributions
for velocity, temperature and their gradients. The Runge- Kutta method together with
shooting technique has been used to solve the BVP to yield temperature and its gradients
for different sets of parameter values. Thus numerically computed values for the velocity,
temperature and their gradientsare readily exploited to compute entropy generation and
-
Entropy Generation Analysis for... 161
Bejan number depicted in figures 1-18. Figure 1 shows the effect of Brinkman number on
non dimensional temperature θ(η).We observe that the thickness of thermal boundary
layer registers an increase with an increment in values of Brinkman number. This goes
fine with reasoning that larger values of Brinkman number indicate more frictional
heating in the system causing a rise of temperature θ(η). The effect of magnetic field has
been depicted in Figure 2, which shows that θ(η) increases with increasing values of
Hartmann number M. Figure 3 demonstrates variation of θ(η) for different values of
Prandtl number Pr. We find that θ(η) decreases with an increase in Pr. The effect of
radiation parameter N on θ(η) has been shown in figure 4, which demonstrates that the
temperature θ(η) registers a considerable increase with an increase in radiation parameter
N. Figure 5 exhibits variations in θ(η) for different values of Reynolds number Re. It
clearly shows that increase in Re results in decay of θ(η). Figure 6 shows the impact of
permeability parameter K on the temperature. We find that the temperature decreases
with the increase in permeability parameter K.
Figure 7-18 depict variation in entropy generation number and in Bejan number for varying
values of pertinent parameters. The plots for Bejan number show that there is a rise in
Bejan number in a region adjacent to the surface and after attaining a peak at different
spatial distances the Be decreases as we move farther away from the surface. Figure 7
demonstrates that the effect of Brinkman number over entropy generation number. The
figure reveals that the entropy increases with an increase in Brinkman number. Figure 8
shows that Bejan number decreases throughout the solution space with an increase in the
values of Br. Figure 9 and Figure 10 display the effect of permeability parameter K on
entropy generation number and Bejan number respectively. It is revealed that with an
increase in values of K there is a decay in entropy where as the Bejan number increases
with increasing K in the region adjacent to the surface though it decreases subsequently
with increasing values of K. Figure 11 and Figure 12 depict the effects of magnetic field
parameter M on entropy and Bejan number. Figure 11 shows that with an increase in
magnetic parameter M, the entropy increases. The Bejan number decreases with increasing
values of M near the surface till a certain spatial distance and then increases. Figure 13
exhibits the effect of radiation parameter N on entropy generation number. It shows that
with increasing values of N, the entropy decays near the surface and then the trend is
reversed beyond a certain spatial distance. Figure 14 depicts the decrement of Bejan
number Be with an increment in the values of radiation parameter N. Figure 15 and figure
16 depict the effect of ω on the entropy generation number and Bejan number respectively.
We find that the entropy increases with an increase in ω whereas the Bejan Number
decreases with the increasing values of ω. Figure 17 and figure 18 demonstrate the effect of
Reynolds number Re on entropy generation number and the Bejan number respectively. It
is shown that the entropy decreases with an increase in Reynolds number whereas Bejan
number increases near the surface and then the trend is reversed.
6. Conclusion
It is found that the parameters entering into the problem have qualitative and quantitative
bearing on entropy generation number and the Bejan number. The information can be
utilized for entropy minimization.
-
162 Paresh Vyas and Kusum Yadav
Fig 1 Temperature Profiles for varying
values of Brinkman number Br
Fig 4 Temperature Profiles for varying
values of radiation parameter N
Fig 2 Temperature Profiles for varying
values of Hartmann number M
Fig 5 Temperature Profiles for varying
values of Reynolds number Re
Fig 3 Temperature Profiles for varying
values of Prandtl number Pr
Fig 6 Temperature Profiles for varying
values of permeability parameter K
-
Entropy Generation Analysis for... 163
Fig 7 Entropy generation number for
varying values of Brinkman number Br
Fig 10 Bejan number for varying values of
permeability parameter K
Fig 8 Bejan number for varying values of
Brinkman number Br
Fig 11 Entropy generation number for
varying values of Hartmann number M
Fig 9 Entropy generation number for varying
values of permeability parameter K
Fig 12 Bejan number for varying values of
Hartmann number M
-
164 Paresh Vyas and Kusum Yadav
Fig 13 Entropy generation number for
varying values of Radiation paramrter N
Fig 16 Bejan number for varying values of
characteristic ratio ω
Fig 14 Bejan number for varying values of
Radiation parameter N
Fig 17 Entropy generation number for
varying values of Reynolds number Re
Fig 15 Entropy generation number for
varying values of characteristic ratio ω
Fig 18 Bejan number for varying values of
Reynolds number Re
Acknowledgements : The authors are thankful to the Referee for valuable comments and
suggestions.
-
Entropy Generation Analysis for... 165
References
[1] Abel, M.S., Datti, P.S. and Mahesha, N. (2009). Flow and heat transfer in a power-law fluid over a stretching sheet with variable thermal conductivity and
non-uniform heat source, Int. J. of Heat and Mass Transfer, 52, 2902–2913.
[2] Akkayya, B. and Talla, H (2017). Homotopy analysis to heat transfer of visco-elastic fluid through a porous medium over an exponentially stretching sheet with
non uniform heat source/sink, Int. J. Pharm. And Tech. 9(4) 31108-31119.
[3] Bejan A. (1979). A study of entropy generation in fundamental convective heat transfer, J. Heat Transf. 101, 718-725.
[4] Bejan A. (1982). Second-law analysis in heat transfer and thermal design, Adv. in Heat Transf. 15, 1-58.
[5] Bejan A. (1996). Entropy Generation Minimization. CRC Press, Boca Raton, FL, USA.
[6] Bujurke, N.M., Birader, S.N. and Hiremath, P. S. (1987). Second order fluid flow over a stretching sheet with heat transfer, ZAMP, 38(4), 653-657.
[7] Chauhan, D.S. and Olkha A. (2011). Entropy generation and heat transfer effects on non-Newtonian fluid flow in annular pipe with naturally permeable
boundaries, Int J. Energy Technol. 3(30), 1-9.
[8] Chauhan, D.S. and Rastogi, P. (2011). Heat transfer and entropy generation in MHD flow through a porous medium past a stretching sheet, Int. J. Energy
Technol. 3(15), 1-13.
[9] Chauhan, D.S.and Kumar, V. (2011). Heat transfer and entropy generation during compressible fluid flow in a channel partially filled with a porous medium, Int.J.
Energy Technol. 3 (14) ,1-10
[10] Crane, L.J. (1970). Flow past a stretching plate, Z. Angew. Math. Phys. 21, 645-647.
[11] Dehsara, M., Habibi, M. and Dalir, N. (2012). Entropy analysis for MHD flow over a non linear streching inclined transparent plate embedded in a porous
medium due to solar radiation, Mechanika, 18, (5), 524-533.
[12] Gupta, P.S. and Gupta, A.S. (1977). Heat and mass transfer on a stretching sheet with suction or blowing, Can. J. Chem. Eng. 55, 744-746.
[13] Habibi Matin, M., Dehsara, M. and Abbassi, A. (2012). Mixed convection MHD flow of nanofluid over a non-linear stretching sheet with effects of viscous
dissipation and variable magnetic field, Mechanika, 18(4), pp. 415-423.
[14] Heydari, M.R. and Taleghani, A.S. (2016). Analysis of boundary layer in MHD flow of non-Newtonian visco-elastic fluid on stretching sheet, Bulletin de la
Société Royale des Sciences de Liège, 85, 21-33.
-
166 Paresh Vyas and Kusum Yadav
[15] Hooshmand, P., Gatabi, H.R., Bagheri, N., Pirzadeh, I., Hesabi, A., Jamalabadi, M.Y.A. and Oveisi, M. (2017). Numerical study of the magnetic field effects on
the heat transfer and entropy generation aspects of a power law fluid over an
axisymmetric stretching plate structure, Entropy, 19, 94.
[16] Imtiaz, M., Hayat, T. and Alsaedi, A. (2016). MHD Convective Flow of Jeffrey Fluid Due to a Curved Stretching Surface with Homogeneous-Heterogeneous
Reactions, PLoS ONE, 11(9): e0161641,https://doi.org/10.1371/journal.pone.0161641.
[17] Khan, M. and Rahman, M. (2015). Flow and heat transfer of a modified second order fluid over non linearly stretching sheet, AIP Advances, 5(8), 2158-3226.
[18] Lin, Y. and Chen, C.K. (2017). Analyzing irreversibility of heat transfer for a Non-Newtonian power-law flow with power-law temperature using differential
transform method, Academia J. of Scientific Research 5(11), 577-586.
[19] M.H. Yazdi I. Hashim, I., Fudholi, A., Ooshaksaraei, P. and Sopian, K. (2014). Entropy generation analysis of power-law Non-Newtonian fluid flow caused by
micropatterned moving surface, Hindawi Publishing Corporation, 2014, 1-16.
[20] Mahmud S. and Fraser, R.A. (2002). Thermodynamic analysis of flow and heat transfer inside channel with two parallel plates, Exergy, 2, 140-146.
[21] Makinde, O.D.; Aziz, A. (2010). Second law analysis for a variable viscosity plane Poiseuille flow with asymmetric convective cooling, Comput. Math.
Appl. 60, 3012-3019.
[22] Nataraja, H.R., Sharma, M.S., and Rao, B.N. (1998). Flow of a second order fluid over a stretching sheet having power law temperature, Acta Mech. 128, 259-262.
[23] Noghrehabadi, A., Saffarian, M.R., Pourrajab, R. and Ghalambaz, M. (2013). Entropy analysis for nanofluids flow over a stretching sheet in the presence of
heat generation/absorption and partial slip, J. Mech. Sci. Technol., 27(3), 927-937.
[24] Pillai, K.M.C, Sai, K.S., Swamy, N.S., Nataraja, H.R., Tiwari, S.B. and Rao, B.N. (2004). Heat transfer in a viscoelastic boundary layer flow through a porous
medium, Computational Mech. 34, 27-37.
[25] Rashidi, M.M.; Mohammadi, F.; Abbasbandy, S.; Alhuthali, M.S. (2015). Entropy Generation Analysis for Stagnation Point Flow in a Porous Medium over
a Permeable Stretching Surface, Journal of Applied Fluid Mechanics, Vol. 8(4),
pp.753-765.
[26] Rashidi, M.M., Abelman, S. and Freidoonimehr, N. (2012b). Entropy generation in steady MHD flow due to a rotating porous disk in a nanofluid’, International
Journal of Heat and Mass Transfer, Vol. 62, pp.515–525.
[27] Rashidi, M.M., Bagheri, S., Momoniat, E. and Freidoonimehr, N. (2017). Entropy analysis of convective MHD flow of third grade non-Newtonian fluid
over a stretching sheet, Ain Shams Engineering Journal, 81, pp.77-85.
-
Entropy Generation Analysis for... 167
[28] Sakiadis, B.C. (1961). Boundary - layer behavior on continuous solid surface: II. The Boundary - layer on a continuous flat surface, AIChE J. 7, 221-225.
[29] Sakiadis, B.C. (1961). Boundary - layer behavior on continuous solid surfaces: I. Boundary - layer equations for two dimensional and axisymmetric flows, AIChE
J. 7, 26-28.
[30] Srivastava, N., Vyas, P. and Soni, S. (2016). Entropy generation analysis for oscillatory flow in a vertical channel filled with porous medium, International
Conference on Recent Advances and Innovations in Engineering (ICRAIE),
Jaipur, 1-6 10.1109/ ICRAIE.2016.7939542.
[31] Tsou, F.K., Sparrow, E.M. and Goldstein, R.J. (1967). Flow and heat transfer in the boundary layer on a continuous moving surface, Int. J. Heat and Mass
Transfer, 10, 219-235.
[32] Vajravelu, K. and Rollins, D. (1991) Heat transfer in a viscoelastic fluid over a stretching sheet, J. Math. Anal. Appl. 158, 241–255.
[33] Vijaya Laxmi, T., Shankar, B. (2016). Radiative boundary layer flow and heat transfer of nanofluid over a nonlinear stretching sheet with slip conditions and
suction, Jordan Journal of Mechanical and Industrial Engineering, 1(4), 285-297.
[34] Vyas, P. and Rai, A. (2013). Entropy regime for radiative MHD Couette flow inside a channel with naturally permeable base, Int. J. Energy Technol. 5, 1-9.
[35] Vyas, P. and Srivastava, N. (2015). Entropy Analysis of Generalized MHD Couette Flow Inside a Composite Duct with Asymmetric Convective Cooling,
Arabian Journal for Science and Engineering. 40, 603–614.
[36] Vyas, P., Srivastava, N. (2015). Entropy analysis for magnetohydrodynamic fluid flow in porous medium due to non isothermal stretching sheet. Journal of
Rajasthan Academy of Physical Sciences. 14, 323-336.
[37] Vyas, P. and Khan, S. (2016). Entropy analysis for MHD dissipative Casson fluid flow in porous medium due to stretching cylinder. Acta Technica, 61, 299-315.
[38] Vyas, P. and Soni, S. (2018). Entropy analysis for boundary layer flow due to a point sink at the vertex of a cone, Acta Technica, 63(2), 143-156.
[39] Vyas, P. and Soni, S. (2017). On entropy generation in radiative MHD boundary layer flow with partial slip due to a melting surface stretching in porous medium.
Journal of Rajasthan Academy of Physical Sciences, 16(1, 2), 93-111.
[40] Zaib, A., Bhattacharyya, K., Uddin, M. S. and Shafie, S. (2016). Dual solutions of Non-Newtonian Casson fluid flow and heat transfer over an exponentially
permeable shrinking sheet with viscous dissipation, Hindawi Publishing
Corporation Modelling and Simulation in Eng. 2016, 1-8.
https://link.springer.com/journal/13369