Applied Mathematical Sciences, Vol. 4, 2010, no. 32, 1583 - 1606 Heat Transfer in Peristaltic Flow of Viscoelastic Fluid in an Asymmetric Channel 1 A. M. Sobh, 2 S. S. Al Azab and 3 H. H. Madi 1 Department of Mathematics, Faculty of Applied Science, Al Aqsa University Gaza, P.O. Box 4051, Palestine [email protected]2 Head of Mathematics Department, Faculty of Science for Girls Ain Shams University, Egypt. 3 Department of Mathematics, College of Science and Technology, Khan Younis, Palestine E-mail:[email protected]Abstract In this paper, we carry out a study of peristaltic flow of Oldroyd fluid in an asymmetric channel in the presence of heat transfer. The governing equations of motion and energy are simplified using along wave length approximation. A closed form solution for the axial velocity and the temperature is obtained using perturbation method. Furthermore, The effect of various parameters of interest on axial velocity, temperature and heat transfer coefficient are discussed numerically and explained graphically. Mathematics Subject Classification: 76Z05 Keywords: Asymmetric channel; Viscoelastic fluid; Peristalsis; Heat transfer 1 Introduction The peristaltic flow of biofluids in different geometries has many application in mathematics, biology and engineering. The initial mathematical models of peristalsis obtained by a train of sinusoidal waves in an infinitely long symmetric channel or tube have been investigated by Shapiro et al. [2] and Fung and Yih [17].
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2Head of Mathematics Department, Faculty of Science for Girls Ain Shams University, Egypt.
3Department of Mathematics, College of Science and Technology, Khan Younis, Palestine E-mail:[email protected]
Abstract In this paper, we carry out a study of peristaltic flow of Oldroyd fluid in an asymmetric channel in the presence of heat transfer. The governing equations of motion and energy are simplified using along wave length approximation. A closed form solution for the axial velocity and the temperature is obtained using perturbation method. Furthermore, The effect of various parameters of interest on axial velocity, temperature and heat transfer coefficient are discussed numerically and explained graphically. Mathematics Subject Classification: 76Z05 Keywords: Asymmetric channel; Viscoelastic fluid; Peristalsis; Heat transfer 1 Introduction The peristaltic flow of biofluids in different geometries has many application in mathematics, biology and engineering. The initial mathematical models of peristalsis obtained by a train of sinusoidal waves in an infinitely long symmetric channel or tube have been investigated by Shapiro et al. [2] and Fung and Yih [17].
1584 A. M. Sobh, S. S. Al Azab and H. H. Madi After these studies, many investigations were done to understand the peristaltic action for Newtonian and non Newtonian fluids in different situations. The importance of the study of peristaltic transport in an asymmetric channel has been brought out by Eytan and Elad [13] with an application in intra uterine fluid flow in anon-pregnant uterus. After this study, some investigations were done to understand the mechanism of peristalsis in asymmetric channels. Mishra and Rao [10] have investigated the flow in an asymmetric channel generated by peristaltic waves propagating on the walls with different amplitudes and phases. Rao and Mishra [5] discussed the non-linear and curvature effects on the peristaltic flow of a viscous fluid in asymmetric channel when the ratio of channel width to the wavelength is small. Ebaid [1] studied the effects of magnetic field and wall slip condition on the peristaltic transport of a Newtonian fluid in an asymmetric channel. Also Kothandapani and Srinivas [9] discussed the non-linear peristaltic transport of a Newtonian fluid in an inclined asymmetric channel through a porous medium. Furthermore, Haroun [8] studied the effect of wall compliance on peristaltic transport of a Newtonian fluid in an asymmetric channel . In their paper, Hayat et al.[16] investigated the peristaltic mechanism of a Maxwell fluid in asymmetric channel and Subba Reddy et al. [11] investigated the peristaltic motion of a power-low fluid in an asymmetric channel. Also Ali and Hayat [12] studied the peristaltic motion of a Carreau fluid in an asymmetric channel. Furthermore, Sobh[3] studied the slip flow in peristaltic transport of a Carreau fluid in an asymmetric channel and Wang et al.[18] have studied the magnetohydrodynamic peristaltic flow of a Sisko fluid in a symmetric or asymmetric channel. Recently, few studies have been done to understand the interaction between heat transfer and peristaltic flow for Newtonian fluids. Srinivas and Kothandapani [15] investigated the peristaltic transport of a Newtonian fluid with heat transfer in an asymmetric channel. Sobh [4] studied the slip flow of peristaltic transport of a magneto-Newtonian fluid through a porous medium with heat transfer. Also Mekhheimer and Abd elmaboud [7] studied the influence of heat transfer and magnetic field on peristaltic transport of a Newtonian fluid in a vertical annulus. Furthermore, Radhakrishnamacharya and Srinivasulu [6] investigated the influence of wall properties on peristaltic transport with heat transfer. Since it is well known that physiological fluids behave like non-Newtonian fluids, we'll study the heat transfer in peristaltic flow of Oldroyd fluid, as a viscoelastic fluid, in an asymmetric channel with peristaltic waves of different amplitudes and phase traveling on its walls. The problem is formulated and analyzed using perturbation series on the wave number as a parameter. Because of the complexity of the governing equation, long wavelength approximation is used to obtain analytic expressions for the axial velocity, the temperature and the heat transfer coefficient. Moreover, the influences of Reynolds number, phase difference, Weissenberg number, wave number, Prandtl number, Eckert number and channel
Heat transfer in peristaltic flow of viscoelastic fluid 1585 width on axial velocity, temperature and heat transfer coefficient have been discussed. 2 Formulation and Analysis Let us consider a two-dimensional flow of Oldroyd fluid in an asymmetric channel. We assume sinusoidal wave train moving with speed c along the channel walls. The upper wall is maintained at temperature 0T and the Lower wall at 1T . Let
21 dd + be the channel width. Taking X and Y as rectangular coordinates, the geometry of the wall surfaces are defined as
( ) ,)(2cos, 111 ⎥⎦⎤
⎢⎣⎡ −+= tcXadtXhλπ upper wall, (1)
( ) ( ) ,2cos, 222 ⎥⎦⎤
⎢⎣⎡ +−−−= φλπ tcXadtXh lower wall, (2)
Where 1a , 2a are the amplitudes of the waves, λ is the wavelength, t is the time and φ ( πφ ≤≤0 ) is the phase difference. Moreover, ,1a 2a , ,1d 2d and φ satisfy the following inequality, Mishra and Rao [10],
( ) .cos2 22121
22
21 ddaaaa +≤++ φ
The constitutive equation for Oldroyd fluid is
( ) ( )
( ) jijjj
kikii
kk
iii
kkjjj
kkij
jjiikkjjii
kkijij
vgx
gg
vgx
ggggx
vgggt
γμτ
τττ
τ
&−=⎥⎦
⎤∂∂
−
⎢⎢⎣
⎡
∂∂
−∂∂
∂
∂Γ+ )(2
1
(3)
where iig and jjg are respectively the diagonal components of covariant and contravariant metric tensor, ji, =1,2.
Taking moving coordinates ( )yx, , (wave frame), which travel in the X -direction with the same speed, as the wave, the unsteady flow in the laboratory frame ( )YX , can be treated as steady, Shapiro et al. [2]. The coordinates frame are related through
YytcXx =−= , , (4) VvcUu =−= , , (5)
where ( )VU , and ( )vu , are the velocity components in the corresponding coordinate system. Equations of motion in the moving coordinates are, Rathy [14]
1586 A. M. Sobh, S. S. Al Azab and H. H. Madi
0=∂∂
+∂∂
yv
xu (6)
yxxp
yuv
xuu xyxx
∂
∂−
∂
∂−
∂∂
−=⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂ ττ
ρ (7)
yxyp
yvv
xvu yyyx
∂
∂−
∂
∂−
∂∂
−=⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂ ττ
ρ (8)
The constitutive equations of Oldroyd fluid are, Rathy[14]
xxyxxxxxxx
xx yu
xu
yv
xu γμττ
τττ &−=⎥
⎦
⎤∂∂
−∂∂
−∂
∂⎢⎣
⎡+
∂
∂Γ+ 22 (9)
yxxxyyyxyx
yx xv
yu
yv
xu γμττ
τττ &−=⎥
⎦
⎤∂∂
−∂∂
−∂
∂⎢⎣
⎡+
∂
∂Γ+ (10)
yyyyyxyyyy
yy yv
xv
yv
xu γμττ
τττ &−=⎥
⎦
⎤∂∂
−∂∂
−∂
∂⎢⎣
⎡+
∂
∂Γ+ 22 , (11)
The differential energy equation is
⎥⎦
⎤⎢⎣
⎡
∂∂
+∂∂
+∂∂
+∂∂
+∇=⎥⎦
⎤⎢⎣
⎡
∂∂
+∂∂
xv
yu
yv
xuTk
yTv
xTuC yxyyxxv τττρ 2 , (12)
where p is the pressure, xxτ , yxτ , yyτ are components of the extra stress tensor, Γ is relaxation time, μ is the coefficient of viscosity of the fluid,σ is the electrical conductivity, vC is the specific heat at constant volume, ν is kinematic viscosity, k is
thermal conductivity of the fluid, T is temperature and xxγ& , yxγ& , yyγ& are components of strain-rate tensor and given by
,2,2yv
xu
yyxx ∂∂
=∂∂
= γγ && and ,⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
=xv
yu
yxγ& (13)
Introducing the non-dimensional variables and parameters
jiij cd
dhh
dhhtct
cdvv
cuu
dyyxx τ
μτ
λλ
λ1
1
22
1
11
11
,,,,,,, ======== ,
jijiie cdp
cdp
dcWdcRd
γγλμμ
ρλ
δ && 12
1
1
11 ,,,, ==Γ
=== ,01
0
TTTT
−−
=θ ,
k
CP v
rμ
= ,)( 01
2
TTCcE
v −= , (14)
Heat transfer in peristaltic flow of viscoelastic fluid 1587 whereδ is the wave number, eR is the Reynolds number, iW is the Weissenberg number, θ is the dimensionless temperature, rP is the Prandtl number and E is the Eckert number, equations (6-12) are reduced to
0=∂∂
+∂∂
yv
xu (15)
yxx
pyuv
xuuR yxxx
e ∂
∂−
∂∂
−∂∂
−=⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂ ττ
δδ , (16)
yxy
pyvv
xvuR yyxy
e ∂
∂−
∂
∂−
∂∂
−=⎥⎦
⎤⎢⎣
⎡⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
+∂∂ τ
δτ
δδ 23 , (17)
xu
yu
xu
yv
xuWi xyxx
xxxxxx ∂
∂−=⎥
⎦
⎤⎢⎣
⎡∂∂
−⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
−∂∂
+∂∂
+ δττττ
δτ 222 , (18)
⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
−=⎥⎥⎦
⎤
⎢⎢⎣
⎡
∂∂
−⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
−∂
∂+
∂
∂+
xv
yu
yu
xv
yv
xuWi yyxx
xyxyxy
2δτδτττ
δτ , (19)
xv
xv
yv
yv
xuWi xyyy
yyyyyy ∂
∂−=
⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
−∂∂
−∂
∂+
∂
∂+ δδττ
ττδτ 222 . (20)
+⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
+⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
=⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
yv
xuE
xyPyv
xuR yyxx
re ττδθδθθθδ 2
22
2
21
⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
xv
yuE xy
2δτ (21)
Eliminating the pressure from equation (16), (17) we get
⎥⎦
⎤⎢⎣
⎡⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
−∂∂
+∂∂
−∂∂
2
2
2
22
2
2
2
2
xuv
xvu
yvu
yuvRe δδ =
⎟⎟⎠
⎞⎜⎜⎝
⎛
∂∂∂
−∂∂
∂+
∂
∂−
∂
∂
xyyxyxxxyyyxxy ττ
δττ
δ22
2
2
2
22 (22)
3 Rate of Volume Flow and Boundary Conditions The dimensional volume flow rate in laboratory frame is
( )( )
( )YdtYXUQ
tXh
tXh∫=
,1
2 ,
,, , (23)
1588 A. M. Sobh, S. S. Al Azab and H. H. Madi in which 1h and 2h are function of X , t The rate of volume flow in the wave frame is given by
( )( )
( )ydyxuq
xh
xh∫=1
2
, , (24)
where 1h and 2h are function of x only. On substituting Eqs. (4) and (5) into Eq. (23) and then integrating, we have )()( 21 xhcxhcqQ −+= (25) The time- mean flow over a period T is defined as
∫=T
tQdT
Q0
1 (26)
Substituting (25) into (26), and integrating, we get 21 dcdcqQ ++= . (27) Defining the dimensionless mean flows θ and F as follow
1dc
Q=θ and
1dcqF = , (28)
Equation (27) may be written as dF ++= 1θ , (29) where
( )
( )
dyuFx
h
xh∫=1
2
. (30)
We note that ( )xh1 and ( )xh2 represent the dimensionless forms of the wall surfaces and defined by ( )xh1 =1+a cos 2π x and ( ) =xh2 -d-b cos ( )φπ +x2 , (31)
where 2
2
1
1 ,da
bda
a == , and 1
2
dd
d = ,
and a, b, d and φ satisfy the relation ( )222 1cos2 dabba +≤++ φ . (32) The boundary conditions for the dimensionless in the wave frame is ,1−=u at y= ( )xh1 , (33-a) .1−=u at y= ( )xh2 . (33-b)
dxdh
v 1−= , at )(1 xhy = , (34-a)
Heat transfer in peristaltic flow of viscoelastic fluid 1589
dxdh
v 2= . at )(2 xhy = . (34-b)
0=θ , at )(1 xhy = , (35-a) 1=θ . at )(2 xhy = . (35-b) 4 Method of Solution We expand the following in a power series of small parameter δ as follows ( )2
The use of expansions (36) with Eqs. (15), (16), (17), (18), (19), (20),(21),(22) and boundary conditions (33),(34),(35) we get system of order zero
000 =∂∂
+∂∂
yv
xu
, (37)
yx
p yx
∂
∂−=
∂∂ )0(
0 τ, (38)
( ) ( ) 02 000 =∂∂
−yu
Wi xyxx ττ , (39)
( ) ( )
yu
yu
Wi yyxy ∂∂
−=∂∂
− 0000 ττ , (40)
( ) 00 =yyτ , (41)
⎥⎦
⎤⎢⎣
⎡∂∂
+⎥⎦
⎤⎢⎣
⎡∂∂
=yu
EyP xy
r
0)0(20
210 τθ
, (42)
1590 A. M. Sobh, S. S. Al Azab and H. H. Madi
02
)0(2
=∂
∂
yxyτ
. (43)
With the dimensionless boundary conditions ,10 −=u at ( )xhy 1= , (44-a) .10 −=u at ( )xhy 2= . (44-b)
,10 dx
dhv −= at )(1 xhy = , (45-a)
dxdhv 2
0 = . at )(2 xhy = . (45-b)
00 =θ , at ),(1 xhy = (46-a) .10 =θ at ).(2 xhy = (46-b) The solution of (41),(40)and (38),subject the boundary conditions(44-a)and(44-b),is
[ ] 1)(21),( 2121
200 −++−⎥⎦
⎤⎢⎣⎡∂∂
= hhyhhyx
pyxu (47)
The instantaneous volume flow rate, 0F ,is given by
[ ] [ ]213
120
200 12
11
hhhhxp
dyuFh
h
−−−⎥⎦⎤
⎢⎣⎡∂∂
== ∫ (48)
The zero-order pressure gradient can be obtained by solving (48) for dxdp0 ,as
( )( )312
2100 12hh
hhFdxdp
−−+
= (49)
Substituting dx
dp0 into(47),we obtain the form of 0u as
322
10 ),( LyLyLyxu ++= (50)
where 312
2101 )(
)(6hh
hhFL
−−+
= , 312
212102 )(
))((6hh
hhhhFL
−+−+−
= ,
and 1)(
)(63
12
212103 −
−−+
=hh
hhhhFL . (51)
Substituting ),(0 yxu from (50) into(37),and then solving the equation , subject the boundary condition(45-a),we obtain the form of 0v as
)(21
31),( 1
321
231
10 xGyLyLyLyxv +−−−= (52)
where 113
21
12
31
11
11 2
131)( hLhLhLhxG +++−= . (53)
Heat transfer in peristaltic flow of viscoelastic fluid 1591 Substituting ),(0 yxu from (50)and(40) into (42),subject the boundary conditions(46-a)and(46-b),we obtain the form of 0θ as 54
23
32
410 ),( ByByByByByx ++++=θ (54)
where 211 3
1 ELPB r= , 212 32 LELPB r= , 2
23 21 ELPB r= ,
,)(21)(
32)(
311
)(1 2
122
22
31
3221
41
42
21
124 ⎥
⎦
⎤⎢⎣
⎡⎥⎦⎤
⎢⎣⎡ −+−+−−
−= hhLhhLLhhLEP
hhB r
and ⎥⎦
⎤⎢⎣
⎡⎥⎦⎤
⎢⎣⎡ −+−+−+−
−= )(
21)(
32)(
311 12
22
21
2221
31
32
212
12
15 hhLhhLLhhLEhP
hhhB r .(55)
System of order one Equating the coefficients of δ on both sides in Eqs. (15), (16), (17), (18), (19), (20),(21),(22),(33),(34) and (35) we get
011 =∂∂
+∂∂
yv
xu
(56)
( ) ( )
yxxp
yu
vx
uuR yxxx
e ∂
∂−
∂∂
−∂∂
−=⎥⎦
⎤⎢⎣
⎡⎟⎟⎠
⎞⎜⎜⎝
⎛∂∂
+∂∂ 10
100
00
ττ, (57)
( )( ) ( )
( ) ( ) ( )
xu
yu
yu
xu
yv
xuWi xyxyxx
xxxxxx ∂
∂−=⎥
⎦
⎤⎢⎣
⎡∂∂
−∂∂
−∂∂
−∂∂
+∂∂
+ 00110000
0
0
01 2222 τττ
τττ ,(58)
( )( ) ( )
( ) ( )
yu
yu
yu
yv
xuWi yyyy
xyxyxy ∂
∂−=
⎥⎥⎦
⎤
⎢⎢⎣
⎡
∂∂
−∂∂
−∂
∂+
∂
∂+ 10110
0
0
0
01 ττ
τττ , (59)
( )( ) ( )
( )
xv
yv
yv
xuWi yy
yyyyyy ∂
∂−=
⎥⎥⎦
⎤
⎢⎢⎣
⎡
∂∂
−∂
∂+
∂
∂+ 000
0
0
0
01 22τ
τττ , (60)
+⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
+⎥⎦
⎤⎢⎣
⎡∂∂
=⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
yv
xu
EyPy
vx
uR yyxxr
e0)0(0)0(
21
20
00
01 ττ
θθθ
⎥⎦
⎤⎢⎣
⎡∂∂
+∂∂
yu
yuE xyxy
0)1(1)0( ττ (61)
( ) ( ) ( )
xyyxyyv
uyu
vR xxyyyxe ∂∂
∂−
∂∂
∂+
∂
∂−=⎥
⎦
⎤⎢⎣
⎡∂∂
−∂∂ 0202
2
12
20
2
020
2
0τττ
, (62)
with the boundary conditions 01 =u at ( )xhy 1= (63-a)
1592 A. M. Sobh, S. S. Al Azab and H. H. Madi 01 =u at ( )xhy 2= (63-b) 01 =v at )(1 xhy = (64-a) 01 =v at )(2 xhy = (64-b) 01 =θ at )(1 xhy = (65-a) 01 =θ at )(2 xhy = (65-b) Substituting (41),(40),(39),(50),(52) into Eqs. (60), (59), (58), (57) and then solving the resulting system along the boundary conditions (63), we get velocity 1u in the form
+⎥⎦⎤
⎢⎣⎡∂∂
+++++= 2125
344352611 2
121
6122030),( y
xpyAyAyAyAyAyxu
+−+−+−+−+−⎜⎝⎛
−)(
2)(
6)(
12)(
20)(
30)(22
21
532
31
442
41
352
51
262
61
1
12
hhAhhAhhAhhAhhAhh
y
⎟⎟⎠
⎞−⎥⎦
⎤⎢⎣⎡∂∂ )(
21 2
22
11 hh
xp )(
6)(
12)(
20)(
30)(2
122
431
32
341
42
251
52
1
12
21 hhAhhAhhAhhAhh
hh−+−+−+−⎜
⎝⎛
−+
⎟⎟⎠
⎞−⎥⎦
⎤⎢⎣⎡∂∂
+−+ )(21)(
2 121
125 hh
xphhA (66)
where
,31 1
111 LLRA e= [ ])8()(32 11
112112 LLWLLRA ie += ,
)1226()21( 1
111112
11211
132
123
113 LLLLLLWLLLLLLRA ie −++−+= ,
( ) ( )121
112
1122
11311
1234 8428)(2 LLLLLLLLWixGLLLRA e −−+++= ,
( ) ( )1132
11
131
1223
112
1335 2)(4232)( LLxGLLLLLLLWixGLLLRA e +−−−++= . (67)
The instantaneous volume flow rate, 1F ,is given by
−+−+−+−⎥⎦⎤
⎢⎣⎡∂∂
== ∫ 512
21
62
72
712
61
1312
1
211 3(
120)7557(
420)(
1211
hhA
hhhhhhA
hhxp
dyuFh
h
)22(24
)5335(120
)322 321
42
412
31
4421
52
512
41
3521
62
61 hhhhhAhhhhhh
Ahhhh −+−+−+−+−+
.)(12
312
5 hhA
−+ (68)
The one-order pressure gradient can be obtained by solving (68) for dxdp1 ,as
Heat transfer in peristaltic flow of viscoelastic fluid 1593
( )
⎥⎥⎥⎥⎥⎥⎥
⎦
⎤
⎢⎢⎢⎢⎢⎢⎢
⎣
⎡
−+−+
+−−+
+−−+
+−−+
−−++
−=
325
22152
215
315
1324
424
3124
414
4213
5232
413
513
5212
6222
512
612
2611
721
6211
7111
312
1
7021021070
70357035
3521352121142114
14101410840
701
hAhhAhhAhA
hhAhAhhAhA
hhAhAhhAhAhhAhAhhAhA
hhAhAhhAhAF
hhdxdp , (69)
Substituting dxdp1 into(66),we obtain the form of 1u as
)()()(21
26122030),( 32
21
25344352611 xGyxGyxGy
Ay
Ay
Ay
Ay
Ayxu +++++++= (70)
where
,)( 11 dx
dpxG =
,2
)()()(60
)( 121
12
12
xGhhhh
xG+
−−
=η
where )(30)(10)(5)(3)(2 2
22
1532
314
42
413
52
512
62
6111 hhAhhAhhAhhAhhA −+−+−+−+−=η .
and ).(2)(60
)( 121
12
2213 xG
hhhh
hhxG +
−=
η
where )(30)(10)(5)(3)(2 125
21
224
31
323
41
422
51
5212 hhAhhAhhAhhAhhA −+−+−+−+−=η (71)
Substituting ),(1 yxu from (70) into(56),and then solving the equation , subject the boundary condition(64-a),we obtain the form of 1v as
2
)(6
)(62460120210
),(21
231
131
541
451
361
271
11
yxGyxGyAyAyAyAyAyxv −−−−−−−
=
).()(13 xNyxG +− (72)
where
113
21
12
31
11
31
15
41
14
51
13
61
12
71
11 )(
2)(
6)(
62460120210)( hxGhxGhxGhAhAhAhAhAxN +++++++= (73)
Substituting(39),(40),(41),(50),(52),(54),(59)and(60) into (61),subject the boundary conditions(65-a)and(65-b),we obtain the form of 1θ as
+++++++= 273645546372811 261220304256
),( yM
yM
yM
yM
yM
yM
yM
yxθ
)(12
)(20
)(30
)(42
)(56)(
1 42
41
552
51
462
61
372
71
282
81
1
12
hhMhhMhhMhhMhhMhh
−+−+−+−+−⎜⎝⎛
−
1594 A. M. Sobh, S. S. Al Azab and H. H. Madi
+−+−⎜⎝⎛
−+⎟
⎠⎞−+−+ )(
42)(
56)()(
2)(
661
62
271
72
1
12
2122
21
732
31
6 hhMhhMhh
hhyhhMhhM
)(30
51
52
3 hhM
− .)(2
)(6
)(12
)(20 12
721
22
631
32
541
42
4 ⎟⎠⎞−+−+−+−+ hhMhhMhhMhhM (74)
where
),54()
34( 11
111
1111 ALEPLBBLPRM rre +−=
),38()
52()2( 11
12112212
111
12
112
1212 LLEPWALALEPBLBLBLBLPRM rirre −++−−+=
)21
34()
32
234( 22313
112
121
13
113
122
1313 ALALEPBLBLBLBLBLBLPRM rre ++−−−++=
),3
16384( 2
111
11121
112
21 LLLLLLLEPW ri −+−
++−−−++= ))(4313( 14
113
122
13
123
132
1414 xGBBLBLBLBLBLBLPRM re
)322( 3241 ALALEPr + ),
3884
328( 1
12121
12
11221
111
22
113
21 LLLLLLLLLLLLEPW ri −−++−
++++−−++= 425124123
13
133
142
1515 4())(3
212( ALALEPxGBBLBLBLBLBLPRM rre
)),(812864())(4 121
112
22
13
21
11321
1221
113111 xGLLLLLLLLLLLLLLEPWxGL ri −+−+−−
)2)(2)(4())(2( 5212213413
143
1526 ALxGLxGLEPxGBBLBLBLPRM rre ++++−+=
),2102)(8)(42( 22
12
113
22
1321
1132
121
21
1231 LLLLLLLLLLxGLLxGLLLLEPW ri −+−+−+−
)(2)(2())(2())(( 12221
1232224
1537 xGLxGLLLLLEPWxGLEPxGBBLPRM rirre −+−++=
).2 2
213LL− (75)
Substituting ),(0 yxu from (50)and ),(1 yxu from(70)into (36) for ),( yxu we get the axial velocity u in the form
21
2534435261
322
1 )(21
26122030[),( yxG
yAy
Ay
Ay
Ay
ALyLyLyxu ++++++++= δ
)].()( 32 xGyxG ++ (76) Substituting ),(0 yxθ from (54)and ),(1 yxθ from(74)into (36) for ),( yxθ we have temperature θ in the form
5463728154
23
32
41 20304256
),( yMyMyMyMByByByByByx +++⎜⎝⎛+++++= δθ
Heat transfer in peristaltic flow of viscoelastic fluid 1595
+−+−⎩⎨⎧
−++++ )(
42)(
56)(1
261272
71
282
81
1
12
273645 hhMhhMhh
yMyMyM
yhhMhhMhhMhhMhhM
⎭⎬⎫−+−+−+−+− )(
2)(
6)(
12)(
20)(
3022
21
732
31
642
41
552
51
462
61
3
+−+−+−+−⎩⎨⎧
−+ )(
20)(
30)(
42)(
56)(4
142
451
52
361
62
271
72
1
12
21 hhMhhMhhMhhMhh
hh
⎟⎟⎠
⎞
⎭⎬⎫−+−+− )(
2)(
6)(
12 1272
122
631
32
5 hhMhhMhhM (77)
The heat transfer coefficient ( Z ) at the(upper) wall is given by .1 yxhZ θ= (78) Substituting Eq. (77) in Eq. (78), we get
⎜⎜⎝
⎛++++
⎩⎨⎧++++= 3544536271
432
23
11 34567234 yMyMyMyMyMByByByBhZ x δ
)(20
)(30
)(42
)(56
12
52
51
462
61
372
71
282
81
1
127
26 hhMhhMhhMhhMhh
yMyM−+−+−+−⎢⎣
⎡−
+++
⎟⎟⎠
⎞
⎭⎬⎫⎥⎦⎤−+−+−+ )(
2)(
6)(
1222
21
732
31
642
41
5 hhMhhMhhM . (79)
Results and Discussion It is seen form equations (76), (77) and (79) that we have obtained the axial velocity, the temperature and the heat transfer coefficient in explicit form. The effect of the physical parameters of the problem on the axial velocity and the temperature is seen through figures (1-10). Fig (1) shows the effect of the Weissenberg number iW on the axial velocity u
at x=0.2, δ =0.02, E=1, rP =1, eR =10, a=0.5, b=0.7, d=1, θ =1, φ =4π and ( iW =0,
0.04, 0.08). We observe that there is no effect for Weissenberg number iW on the axial velocity as the curves coincide. Fig (2) represents the graph of the axial velocity u versus y at x=0.2, E=1,
rP =1, iW =0.01, eR =10, a=0.5, b=0.7, d=1, θ =1, φ =4π and (δ =0, 0.04, 0.08). It can
be seen that an increase in the wave number δ increase the magnitude of the axial velocity u.
1596 A. M. Sobh, S. S. Al Azab and H. H. Madi The effects of Reynolds number eR on the axial velocity u is seen through
Fig.(3) at x=0.2, δ =0.02, E=1, rP =1, iW =0.04, a=0.5, b=0.7, d=1, θ =1, φ =4π and
( eR =0, 10, 20). It is noted that an increase in the Reynolds number eR increase the magnitude of the axial velocity. Fig.(4) gives the effects of phase difference φ on the axial velocity u at x=0.2,
δ =0.02, E=1, rP =1, iW =0.04, a=0.3, b=0.5, d=0.7, θ =1, eR =10 and (φ =0, 6π ,
4π ).
We have observed that the magnitude of the axial velocity increase with increasing phase difference φ . To see the effects of channel width d on the axial velocity we have prepared Fig.(5). Obviously, the magnitude of the axial velocity increase as d increases. Fig.(6) displays the influence of the Reynolds number eR on the temperature
distribution for x=0, δ =0.02, E=1, rP =1, iW =0.04, a=0.7, b=1.2, d=2, θ =1, φ =4π
and ( eR =90, 80, 70). We note that the temperature θ increases as Reynolds number
eR increases. Fig.(7) shows the effect of the Prandtl number rP on the temperature for x=0,
δ =0.02, E=1, eR =50, iW =0.04, a=0.5, b=0.7, d=2, θ =1, φ =4π and ( rP =1.5, 1.4,
1.3). It is noticed that the temperatureθ increases with increasing the Prandtl number rP .
Fig.(8) depicts the variation of the fluid temperature θ with y, for different value of the Eckert number and at x=0, δ =0.02, rP =1.5, iW =0.04, a=0.5, b=0.7, d=2,
θ =1, eR =50, φ =4π and (E=1, 0.8, 0.6). It is evident that the temperatureθ increases
with the increase in Eckert number E. In Fig. (9), the temperature is graphed versus y at x=0, δ =0.02, E=1, rP =2,
iW =0.04, a=0.5, b=0.7, θ =1, eR =50, φ =4π and (d=2, 1.9, 1.8). We note that the
temperature distribution θ increase as the channel width d increases. Fig.(10) is the graph of temperature distribution versus y for different values of phase difference φ and at x=0, δ =0.02, rP =1, E=1, iW =0.03, a=0.3, b=0.4, d=0.9, θ =1, and eR =10. It can be noticed that an increase in the phase difference φ result increase in the magnitude of the temperature distribution. Variations of the heat transfer coefficient (Z) at wall have been presented in Table(1), (a)-(d). The results reveal that the heat transfer coefficient (Z) increases
Heat transfer in peristaltic flow of viscoelastic fluid 1597 with increasing upper wave amplitude a, Eckert number E, Reynolds number eR and Weissenberg number iW . Concluding Remarks In this paper we presented a theoretical approach to study the effect of heat transfer on peristaltic flow of viscoelastic fluid in an asymmetry channel. The governing equations of motion and energy are solved analytically using perturbation expansion on wave as a parameter. Furthermore, The effect of various values of parameters of interest on axial velocity, temperature and heat transfer coefficient are discussed numerically and explained graphically through figures (1-10). Moreover, the heat transfer coefficient is discussed through table(1). The main results can be summarized as follows : •. There is no appreciable effect of Weissenberg number iW on the axial velocity u. •. The magnitude of the axial velocity increases with increasing wave numberδ , Reynolds number eR , phase difference φ and channel width d. •. The temperatureθ increases with increasing Reynolds number eR , Prandtl number rP , Eckert number E and channel width d . •. The magnitude of the temperature increases with an increase in phase difference φ . •. The heat transfer coefficient (Z) increases with increasing upper wave amplitude a, Eckert number E, Reynolds number eR and Weissenberg number iW . References [1] A. Ebaid, Effect of magnetic field and wall slip condition on the peristaltic
transport of a Newtonian fluid in an asymmetric channel, Phys.Lett.A372(2008),4493-4499.
[2] A.H. Shapiro, M.Y. Jaffrin , S.L. Weinberg, Peristaltic pumping with long
wavelengths at low Reynlod number ,J.Fluid Mech,37 (1969), 799-825. [3] A. M. Sobh, Slip flow in peristaltic transport of a Carreau fluid in an
asymmetric channel, Can.J.Phys.87,(2009),1-9. [4] A. M. Sobh, Heat transfer in a slip flow of peristaltic transport of a magneto-
Newtonian fluid through a porous medium, Inter.J.Biomath., vol.2, No.3, (2009), 299-309.
1598 A. M. Sobh, S. S. Al Azab and H. H. Madi [5] A.R. Rao, and M. Mishra , Nonlinear and curvature effects on peristaltic
flow of a viscous fluid in an asymmetric channel ,Acta Mech.168(2004),35-59.
[6] G.Radhakrishnamacharya and Ch.Srinivasulu, Influence of wall properties on
peristaltic transport with heat transfer, Compt.Rendus Mec.335(2007),369-373.
[7] Kh.S.Mekheimer and Y. Abd elmaboud, The influence of heat transfer and
magnetic field on peristaltic transport of a Newtonian fluid in a vertical annulus: Application of an endoscope, Phys.Lett.A372(2008),1567-1665.
[8] M.H.Haroun ,Effect of wall compliance on peristaltic transport of a Newtonian
fluid in an asymmetric channel, Mathematical Problems in Engineering, Vol. 2006, Article ID 61475,pp.1-19,doi:10.1155/MPE/61475(2006).
[9] M. Kothandapani and S.Srinivas, Non-linear peristaltic transport of a Newtonian
fluid in an inclined asymmetric channel through a porous medium, Phys. Lett. A 372, (2008),1265-1276.
[10] M. Mishra, A.R. Rao, Peristaltic Transport of a Newtonian fluid in an
asymmetric channel, ZAMP54(2003),532-550. [11] M.V. Subba Reddy, A. Ramachandra Rao and S. Sreenadh, Peristaltic motion
of a power-law fluid in an asymmetric channel, Int. J. of Non-linear Mech. 42(2007),1153-1161.
[12] N. Ali and T. Hayat, Peristaltic motion of a Carreau fluid in an asymmetric
channel, Appl. Math. Comput.193 (2007),535-552. [13] O. Eytan and D.Elad, Analysis of Intra-Uterine fluid motion induced by uterine
contraction,Bull.Math.Biology 61 (1999), 221-238. [14] R.K.Rathy,An Introduction to Fluid Dynamics, Oxford and IBH publishing
Co., New Delli, Bombay ,Calcutta.,1976. [15] S.Srinivas and M.Kothandapani, Peristaltic transport in an asymmetric channel
with heat transfer, Inter.Commun.in heat and Mass Trans.35,(2008),514-522. [16] T.Hayat, N. alvi and N.Ali, Peristaltic mechanism of a Maxwell fluid in an
asymmetric channel, Nonlinear Anal. Real World Appl.9,(2008),1474-1490.
Heat transfer in peristaltic flow of viscoelastic fluid 1599 [17] Y.C. Fung and C.S.Yih, Peristaltic transport Transport, J.Appl.Mech.,35
(1968),669-675. [18] Y. Wang, T. Hayat, N. Aliand, M.Oberlack, Magnetohydrodynamic peristaltic
motion of a Sisko fluid in an asymmetric or asymmetric channel, Phy.A387(2008),347-362.
1.6 1.4 1.2 1.0 0.8 0.6 0.4
1.0
0.5
0.0
0.5
1.0
1.5
Fig.1. Axial velocity versus y at x=0.2,δ =0.02,E=1, rP =1, eR =10,a=0.5,b=0.7,d=1,θ =1,4πφ = .
Wi= 0 Wi=0.04 Wi=0.08
u
y
1600 A. M. Sobh, S. S. Al Azab and H. H. Madi
1.2 1.0 0.8 0.6 0.4
0.5
0.0
0.5
1.0
Fig.2.Axial velocity versus y at x =0.2 ,E=1, rP =1,W=0.01, eR =10,a=0.5,b=0.7,d=1,θ =1,4πφ = .
0.38 0.37 0.36 0.35 0.34 0.33
0.0
0.1
0.2
0.3
0.4
Fig.3.Axial velocity versus y at x =0.2 ,E=1,δ =0.02, rP =1,W=0.04,a=0.5,b=0.7,d=1,θ =1,4πφ = .
u
y
δ=0 δ=0.04 δ=0.08
u
y
Re=0 Re=10 Re=20
Heat transfer in peristaltic flow of viscoelastic fluid 1601
0.30 0.25 0.20 0.15 0.10 0.050.4
0.2
0.0
0.2
0.4
0.6
Fig.4.Axial velocity versus y at x =0.2 ,E=1,δ =0.02, rP =1,W=0.04, eR =10,a=0.3,b=0.5,d=0.7,θ =1.
0.26 0.24 0.22 0.20 0.18 0.16 0.14 0.12
0.0
0.2
0.4
0.6
Fig.5.Axial velocity versus y at x =0.,E=1,δ =0.02, rP =1,W=0.04,a=0.5,b=0.5, eR =10,θ =1,4πφ = .
u
y
u
y
φ=0 φ=π/6 φ=π/4
d=0.7 d=0.8 d=0.9
1602 A. M. Sobh, S. S. Al Azab and H. H. Madi
2.0 2.5 3.0 3.5 4.0
2
1
0
1
Fig.6.Temperature distribution y at x =0 ,E=1,δ =0.02, rP =1,W=0.04,a=0.7,b=1.2,d=2, ,θ =1,4πφ =
1.60 1.65 1.70 1.75 1.80 1.85 1.90
0.0
0.5
1.0
Fig.7.Temperature distribution y at x =0 ,E=1,δ =0.02, eR =50,W=0.04,a=0.5,b=0.7,d=2, ,θ =1,4πφ =
θ
y
θ
y
Re=90 Re=80 Re=70
Pr=1.5 Pr=1.4 Pr=1.3
Heat transfer in peristaltic flow of viscoelastic fluid 1603
1.60 1.65 1.70 1.75 1.80 1.85 1.90
0.0
0.5
1.0
Fig .8.Temperature distribution y at x =0 ,δ =0.02, rP =1.5,W=0.04,a=0.5,b=0.7,d=2, eR =50,
θ =1,4πφ = .
2.0 2.2 2.4 2.6
0.5
0.0
0.5
1.0
Fig .9.Temperature distribution y at x =0 ,E=1,δ =0.02, rP =2,W=0.04,a=0.5,b=0.7, eR =50,
θ =1,4πφ =
θ
θ
y
y
E=1 E=0.8 E=0.6
d=2 d=1.9 d=1.8
1604 A. M. Sobh, S. S. Al Azab and H. H. Madi
0.8 0.7 0.6 0.5 0.4 0.3 0.2
1.5
1.0
0.5
Fig.10.Temperature distribution y at x =0 ,E=1,δ =0.02, rP =1,W=0.03,a=0.3,b=0.4,d=0.9,
eR =10,θ =1.
θ
y
φ=0 φ=π/6 φ=π/4
Heat transfer in peristaltic flow of viscoelastic fluid 1605 Table 1
Variation of heat transfer coefficient
(a):δ =0.02,E=1, rP =1, iW =0.04, eR =10,b=1.2,d=1.5,θ =1,φ =4π
x a
0.5 0.7 0.9 1.1
0.1 1.36228 1.38401 1.42048 1.47375
0.2 1.64078 1.67317 1.6991 1.71983
0.3 2.15405 2.72392 3.81008 5.80024
(b):δ =0.02, rP =1,W=0.04, eR =10,a=0.5,b=1.2,d=2,θ =1,4πφ =
x E
1 2 3 4
0.1 1.21571 1.235 1.25429 1.27358
0.2 1.36437 1.41494 1.46551 1.51609
0.3 1.52971 1.57427 1.61882 1.66338
(c):δ =0.02, rP =1,E=1,W=0.04 ,a=0.5,b=1.2,d=1.5,θ =1,4πφ =
x eR
10 2 0 3 0 40
0.1 1.36228 1.40381 1.44535 1.48689
0.2 1.64078 1.75637 1.87196 1.98755
0.3 2.15405 2.61615 3.07824 3.54034
1606 A. M. Sobh, S. S. Al Azab and H. H. Madi
(d):δ =0.02, rP =1,E=1, eR =10 ,a=0.7,b=1.2,d=1.5,θ =1,4πφ =