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Int. J.IndustrialMathematisVol. 3,No. 1(2011)1-7

Exat and Numerial Solutions for Nonlinear

Dierential Equation of Jerey-Hamel Flow

R.Ellahi

Departmentof Mathematis,Faulty ofBasiandAppliedSienesIIUI,H-10 Setor,Islamabad,

Pakistan.

Reeived16February 2011;aepted5May2011.

|||||||||||||||||||||||||||||||-Abstrat

ThispaperlooksattheanalysisofJeeryHamelow. Theinvestigationismainlyaimedto

determineanexatanalytisolutionforanonlinearproblem. Tothebestofmyknowledge,

no suhanalysis isavailablein theliteraturewhihan desribe theexat solutionofthe

Jerey-Hamel ow. Besides this a omparative study between the numerial and exat

solutionsis presented. The eetsof thevariousparameters intrinsito theproblemsare

analyzed and depitedvia graphs.

Keywords: Nonlinearproblem; Exatanalytisolution;NumerialsolutionJerey-Hamelow.

||||||||||||||||||||||||||||||||{

1 Introdution

The ow between two planes whih meet at an angle was rst analyzed by Jeery [7 ℄

and Hamel [6℄. Under suitable assumptions, the problem an be reduedto an ordinary

dierentialequation. The inompressiblevisousuidowthroughonvergent{divergent

hannelsis one of the mostappliable ases inuid mehanis, ivil, environmental,

me-hanialandbio-mehanialengineering. AlotofinformationandreferenesaboutJeery

Hamel ow an be found in the refs. [1, 4, 5 , 13 , 14 ℄. Most sienti problems suh as

Jeery Hamel ows are inherently of nonlinearity. Exept a limited number of these

problem, most of them do not have exat analytial solution. Therefore, these

nonlin-ear equations have been solved either numerially [2 , 15℄ or by perturbation methods

[10 , 11 , 12 ℄. Very little [3 , 8 , 9 ℄ has been yet said in the regime of exat solutions for

nonlinearproblems. Theonvergeneofthesolutionandthelargeparameterare

deien-iesof numerialandtheperturbationmethodsrespetively. We onneourselveshereto

present a general exat analytial solutionand theomparison of numerial solutionas

(2)

well. It is also worth mentioning that our exat analytial solution is not only validfor

smallbutalso forlargevaluesof emergingparameters.

2 Problem formulation

Considerthesteadytwo-dimensionalowof aninompressiblevisousuidfromasoure

or sinkat the intersetion between two rigid plane walls that theangle betweenthem is

2asshowninFig. 1 givenbelow:

Fig. 1. Geometryoftheproblem.

We assume that the veloity is only along radial diretion and depend upon r and

h, i.e., V(u(r;h);0) [10 , 11 ℄. Using ontinuity and the Navier{Stokes equations in polar

oordinateswe have

rr

(ru(r;))=0; (2.1)

u(r;) u(r;) r = 1 p r + 2 u(r;) r 2 + 1 r u(r;) r + 1 r 2 2 u(r;) 2 u(r;) r 2 (2.2) 1 r p + 2 r 2 u(r;) =0:

Equation (2.1) yields

f()ru(r;): (2.3)

Introduing

F( ) f() f max ;= (2.4)

and eliminating p in Eqs. (2.2) and (2.3), we obtainthe following equation for the

nor-malizedfuntionF() as[11℄

F 000

( )+2R e F ()F 0

()+4 2

F 0

()=0: (2.5)

The subjeted orrespondingboundaryonditionsare

F(0)=1;F 0

( 0)=0;F (1)=0; (2.6)

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3 Exat solution

A rstintegralof equation (2.5) is

F 00

+R e F 2 +4 2 F = 1 ; (3.7) where 1

isanarbitraryonstant. Equation(3.7) hasthetranslationalsymmetryinand

its order an be reduedas

1

2 dF

02

dF

+R e F 2 +4 2 F = 1 : (3.8)

Hene we have

F 0 = r 2 1 F 2 3 R eF 3 4 2 F 2 +2 2 ; (3.9) where 2

isa furtheronstant. The boundaryonditions((2.6),b,) then requirethat

1 + 2 = 1 3

R e+2 2

: (3.10)

Sine we want F 0

>0;we omitthenegative signin (3.9). Thus

Z F 1 dE q 2 1 E 2 3 R e E

3 4 2 E 2 + 2 3

R e+4 2

2

1

= (3.11)

subjetto

F (1)=0: (3.12)

isan exat solutionof JeeryHamelow.

4 Numerial Solution

In this setion we present the numerial solution of Jeery Hamel ow by a so alled

method"Shooting method". To applyshootingmethodon Eqs. (2.5) and(2.6), wewrite

ourthirdorder equation inthree rst orderequations

F 0

( )=v( ) (4.13)

F 00

()=u()=v 0

( ) (4.14)

u 0

()= 2R e F()v()+4 2

v()

(4.15)

F (0)=1;v( 0)=0;F (1)=0 (4.16)

and missingonditionis

F 00

( 0)=s or u( 0)=s (4.17)

Equations(4.13)-(4.17) an be dierentiatedwithrespetto sto obtain

F 0

()=V () (4.18)

(4)

U 0

()= 2R e(F

()v()+F()V () )+4 2

V ()

(4.20)

F

(0)=0;V (0)=0;U(0)=1 (4.21)

where

F

= F

s ;V =

v

s ;U =

u

s

(4.22)

and sisan initialguess and hangeiterativelyafter eahstep byNewton'sformula

s n+1

=s n

F (L;s n

) A

F(L;s n

)

s

(4.23)

orhere A=0;L=1 andF=s=F

thentheequation is

s n+1

=s n

F (1;s n

)

F

( 1;s n

)

(4.24)

wheres 1

istaken to be 1:

5 Graphs and omparison of results

In order to illustratethe inuenes ofR

e

and on F; we have plotted theFigures 2and

3 respetively. The obtained analytial solution is ompared with numerial solution in

Figures4 and 5respetively.

(5)

Fig. 3. ProlesofF forvarious valuesofR

e

whenisxed.

(6)

6 Conluding remarks

The present studyontributesexat solutionfortheJerey-Hamel ow. In addition,the

numerialanalysis isalso presentedfor theJerey-Hamelow. Asa result,thefollowing

observationsare made.

InreaseinR

e

resultsintheinreaseof boundarylayer.

An inreasein leadsto anderease intheboundarylayerthikness:

Theonstant >0and<0giveadivergentandonvergent hannelrespetively.

It is also worth mentioning that our exat solutions are more general and suh

solutionshave beenpresentedrst timeintheliterature.

Aknowledgment

RE also thanks Higher Eduation Commission of Pakistan (HEC) for NRPU and

UnitedState EduationFoundationPakistanto honoredhimbyFulbrightSholarAward

fortheyear 2011-2012.

Referenes

[1℄ K.Bathelor,Anintrodutiontouiddynamis.CambridgeUniversityPress,(1967).

[2℄ M.Dehghan,A.Saadatmandi,Thenumerialsolutionofanonlinearsystemof

seond-orderboundaryvalueproblemsusingthesin-olloationmethod,Mathematialand

ComputerModelling, 46 (2007) 1434-1441.

[3℄ C. Feteau, A. Mahmood, Corina Feteau and D. Vieru, Some exat solutions for

thehelialowof ageneralized Oldroyd-Buidina irularylinder,Computers &

Mathematiswith Appliations,56 (2008) 3096-3108.

[4℄ L. E. Fraenkel, Laminar ow in symmetrial hannels with slightlyurved walls. I:

OntheJeery{Hamelsolutionsforowbetweenplanewalls.ProRSoLondA 267

(1962) 119{38.

[5℄ M. Hamadihe, J.Sott and D. Jeandel,Temporal stabilityofJeery{Hamel ow.J

FluidMeh,268 (1994) 71{88.

[6℄ G. Hamel, Spiralformige Bewgungen Zaher Flu ssigkeiten. Jahresberiht der

DeutshenMathVereinigung, 25 (1916) 34{60.

[7℄ G. B. Jeery, The two-dimensional steady motion of a visous uid. Philos Mag, 6

(1915) 455{465.

[8℄ C.M. Khalique, F.M. Mahomed, B.P. Ntsime, Group lassiation of the

(7)

[9℄ F. M. Mahomed and P. G. L. Leah, Symmetry Lie algebras of nth order ordinary

dierentialequations,JournalofMathematialAnalysisandAppliations,151(1990)

80-107.

[10℄ O.D.Makinde,P.Y.Mhone,Hermite{Pade'approximationapproahtoMHDJeery{

Hamelows.ApplMath Comput,181 (2006) 966{72.

[11℄ A. MAlpine, P.G. Drazin, On the spatio-temporal development of small

perturba-tionsofJeery{Hamelows. FluidDyn Res,22 (1998) 123{38.

[12℄ R.K. Rathy, An introdution to uid dynamis. New Delhi: Oxford and IBH Pl,

(1976).

[13℄ L. Rosenhead, The steady two-dimensionalradial ow of visous uid between two

inlinedplanewalls.ProRoySo A175 (1940) 436{67.

[14℄ J.SobeyI,P.G.Drazin,Bifurationsoftwo-dimensionalhannelows.JFluidMeh,

171 (1986)263{87.

[15℄ M.R.Sadri,Channelentrane ow, PhDthesis,Department ofMehanial

References

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