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VNU Journal of Science, Mathematics - Physics 26 (2010) 83-92

Composite cylinder under unsteady, axisymmetric, plane temperature field

Nguyen Dinh

Duc"*,

Nguyen

Thi Thul

,'

universia of

En*ineerins,?::,::l;;':flfrf;:,#irY:::,ii';';;::'''

Hanoi

Received 2 Januarv 2010

Abstract. With advantages such as high strength, high stiffness, high chemical resistance, light weight...composite tubes are widely applied in urban construction and petroleum industry. In this report, the authors used the displacement method

to

study the mechanical behavior (shess, strain...) of an infinite hollow cylinder made of composite material under unsteady, axisymmetric plane temperature field. In the numerical calculations, we mainly studied the influence of time and volume ratio of the particle on the displacement and thermoelastic stress of a cylinder made of Titanium /?VC composite.

1. Introduction

.

ri

Nowadays, composite materials are increasingly promoting

their

preeminences (such as high shock capacity, high thermal-machanical load capacity...) when applied in real structures. The study of thermal-mechanical behavior of composite cylinder has attracted the attention of many authors and series

of

articles have been published on this field. The transient thermal stress problems of multi- layered cylinder as well as hollor composite cylinder are studied in

[14]

by different methods. Iyengar et al. [5] investigated thermal stresses in a finite hollow cylinder due to an axisymmetric temperature

field at the

end surface. Soldatos

et al. [6]

presented

the

three dimensional static, dynamic, thermoelastic

and buckling analysis of

homogeneous

and lamilated

composite cylinders.

Bhattacharyya

et

al.

[7]

obtained the exact solution

of

elastoplastic response

of

an infinitely long composite cylinder during cyclic radial loading. Ahmed et al. [8] studied thermal stresses problem in non-homogeneous transversely isotropic

infinite

circular cylinder subjected

to

certain boundary conditions

by the finite

difference method. Jiann-Quo

Tam [9]

obtained

the

exact solution for functionally graded (FGM) anisotropic cylinders subjected to thermal and mechanical loads. Chao et

al. [10] investigated thermal stresses

in

a vis-coelastic three-phase composite cylinder. The thermal stresses and thermal-mechanical stesses

of FGM

circular

hollow

cylinder subjected

to

certain boundary conditions presented

in

[11-15].

By

using the finite integral transform, Kong et

al.

[16]

obtained the exact solution of thermal-magneto-dynamic and perturbation of magnetic field vector in a non-homogeneous hollow cylinder. Recently, the nonlinear thermoelastic problems of FGM cylinder has also been con-cemed to resolve in

[l7,

18].

h

the articles above, some authors supposed that the material properties depend on both temperatr,re and radius, some other authors assumed that they are independent from the temperature and only depend on the radius r.

* Corresponding author: E-mail: ducnd@vnu.edu.vn 83

(2)

N.D. Duc, N,T. Thuy

/

VNU Journal of Science, Mathematics - Physics 26 (2010) 83-92

In

this paper, based on the goveming equations

of

the theory

of

elasticity, the authors use the displacement method to find the analytical solution for displacement, strain, and thermoelastic stress

of an an infinite hollow cylinder made of particle filled composite material subjected to an unsteady, axis).rnmetric

plane

temperature

field. We

assumed

that the

composite

material is

elastic,

homogeneous and isotropic. We also ignored the interaction between matrix phase and particle phase.

The matenal's thermo-mechanical properties are independent from temperature. There

is

no heat source inside the cylinder. Since the heat flows generated by deformation and the dynamic effects by unsteady heat are minimal, they are also ignored.

2.

Governing equations

(1) '

E= 9KG

3K +G' 2(2* p) 6K +2G' 3\r-2v,) 2\r+v,)

Here

( is

the particle's volume

ratio;

(

l, p),

G,

K, E,

v

, d

are Lame's constants, shear modulus,

bulk

modulus,

Young's

modulus, Poission's

ratio, thermal

expansion coefficient, respectively; the subcripts m and c respectively belong to the matrix phase and particle phase.

In the cylindrical coordinate system (r,0, z) [19]: From the symmetric property, every point is only displaced in the radial direction, so the displacement fi1ed has the form:

u,=u(rrt), u"=ur=0,

The Cauchy relation for strain and displacement are:

er,

= 0uu

fi,

€ee =

2,

€", = €r, = €e, = €re

=

0.

The stress strain relations according to the linear thermoelastic theory are given by

o,, = ),0 + 2p€,, - (3)" +

2

p)a Q - To),

6oe = )'0 + 2Per, - (31+ 2lt)a(T -To), o,, = 1e - Q). + 2p)a (T - To),

T

,o =

T

,, =

T

,e,

where Ze is the initial temperature of the cylinder; 0 = etr + eee .

(2)

(3)

(4)

(3)

N.D. Duc, N.T. Thuy

/

WU Journal of Science, Mathematics - Physics 26 (2010)

83-92

85

When there is no heat source inside the cylinder and the thermal deformation caused of volume change is ignored, the heat conduction equation is expressed in the form

22

1

A

kL'T =

Pc #'

(5)

Here A

=+

+ ^

i i.

the Laplace operator;

k, p,

Care respectively the coefficients ofthermal

dr' r

Or

conductivity, mass density, heat capacity. They are determined as follow

, k=(1- €) k.+€ k"; p=(t-€)p,+€p": , =ffi.

(6)

Since the inertia term is ignored, the equilibrium equation is given by

+*L@.-oee)=0. orr

(7)

Subtitute Eq. (3) and Eq. (4) into Eq. (7) we get

O'u 70u u 3)"+2p

AT

at-; -7 ';'

(8)

Introduce the followins notations

Er::-, ' l-v"' vr=-L-, ar=a(l+v). l-v

(9)

Eq. (8) can be rewritten as

a(ra \ ar

=url=,;trD )=

(r

+ v')a'i;'

(ro)

The initial and boundary conditions of the temperature field are [23]

T

(r,0) =lr

g,tlrf,_o = 1 o,

lar n -l

|

=_ r+Q

_

s,)l - 0,

(11)

l0r ft' "),=o lar a I

l;.?(' -'')l'=u =o'

Here

$,p,

are the temperature

of

the surrounding environment and the surface heat transfer coefficient on the inner edge

r: a; S,

are the corresponding values on the outer edge

r:

b (Te,

9,,9,

considered as constants).

The static boundarv conditions are

o

,,1,=o

= o,

o

,,1,=o

= o.

Q2)

3.

Solution method

By

using the Laplace transform and the Bessel functions,

A.D.

Kovalenko [23] found out the general analytical solution of Eq. (5) with the conditions (11) as below
(4)

86

N.D. Duc, N.T. Thuy

/

WU Journal of Science, Mathematics

-

Physics 26 (2010) S3-g2

r =sz+(,q -z \-r - s;!9!J9^ "" yr*y,4(-yrlnR) -zi.L,,(a4R)e-,:,, -k

(13)

Here: R,=t,R=L,r=5,r,=#,rr=#,r=#,

(14)

A, = ,(n:1,2,...),

(15)

fv. ll-u1

, u.(x)=l v,(r&)+!r,gt47 lt^(*)-l t,(r&)+ !to1at41

ly^@), (m

:

0,

r),

(16)

Lollol

J,(x), Y^(x) (m:0,

1) are the Bessbl functions of orderm of the first and second kinds [20], respectively;

o,

(n

: I,

2,.. .) are the roots of the transcendental equation

ou'.(@,)

Tz =

o.

(17)

uo(a)

The general solution of Eq. (10) may be expressed in the form

D. (l+rt* '

u = D,r +

- rr

+

+ flr - r (a,t)!dr,

Where

D,

D2 are the constants of integration determined from the conditions (12).

Substituting Eq. (.18) into Eq. (3) and the

first

expression of Eqs (4), we have

o,,=Llor+a,(ro-rg,qf - l-vrL-r

E,

--r\-u -'--'-t/-J l+vr12 E, D, *Ero,'!fr r'

!

-r{o,r)frdr, (r9)"

Substituting Eq. (19) into Eq. (12),we find out the constants of integration D,,D,

n, '

=

0r r'r)?r'llT -

T

7o,t)]rdr

arlTo

-

T

(a,t)f;

b"-a"

JL

o,

=

*#o

,11,

- r ro,,)lrdr.

Substituting

Eq. (20)

and

Eq. (13) into

Eq. (18),

we

obtain

the

expresstion

for

the radical displacement

(18)

(20)

+ (r + a

) (a *>+t,"-c")-V, -r{a,t)l r'}.

(2r)

(22a) From Eq. (3) and Eq. (2I), the deformation components of the cylinder can be written as

".=Z[W(q*iau,a') ll b'-d \ n=r )

-(r*r,)(n.r,=,^*4")+lr,(r-r(a,t))+(r-4)]l],

(5)

N.D. Duc, N.T. Thuy

/

WU Journal of Science, Mathematics - Physics 26 (2010) S3-92 87

(22b)

Substitute Eqs. (22a) and (22b) into Eq. (4), we obtain the expressions of thermal stresses in the

o

u

=

T{#(t, * i AnM ne-,i"). (n *f t.I."-+)-lr - r s,41,,1,

rzzat

nn@( n. A^u,"-e,)-v,lr

-r7a,tr1

-(r-4)1.

o==T+r,lb'-d\-'

)

)

Where

b, _

a,

+

b,ln

R

e, =.,

(e,

- s,)i

* ylalt

_

r,tn

R,

u,

- u,f

jon',

,*,o'(rn4

-

M n = (b2

-

a2 )u o(ot,R,

- Lpur(a4) - aur(a,&

)1, (n = 1,2,...),

o)n

L,

= (r2

-

az)uo(at,R,)

-\1rur(a,R) - aur(a,R)f,(n

=1,2,...).

o)n'

4.

Numerical results and discussion

Consider an infinite hollow cylinder made

of

spherical particle frlled composite material. The cylinder has the physical, mechanical and geometrical properties as follows:

a: l0

cm;

b:

10.5 cm;

To =2900

K

'

Properties of PVC matrix: E.=3

GPa,

v, =0.2, d^ =8x10-5K-t, k*

=0.16 Wm.K,

C.

= 900

J/kg.K p-

= 1380

kd-'.

Properties of Titanium:

E" =100 GPa,

v"=0.34, d"=4.8x10{K-1, k"=22.1Wm.K,

C" = 523 J/kg.K,

p.

= 4500

kd*'.

Suppose that the the surroun ing medium on the inner edge

of

cylinder is water with the heat hansfer coefficient 9t = 400 Wlmz

.K

and the stnrounding medium on the outter edge of the cylinder

+ (r + a

) (a *>at,"-c")-V, -r(a,Dl rj.

(23a)

(23c)

,

(24)

(6)

88

N.D. Duc, N.T. Thuy

/

WU Journal of Science, Mathematics - Physics 26 (2010) 83-92

is

air

with

the heat transfer coeffrcientpr=25W1m2.K.

In

order

to

simplify the problem,

in

this paper, we ignore the water pressure on the cylinder wall.

In the following, we

will

investigate the distibution of the radial displacement and the stresses at different radius and particle's volume ratio when the temperatures of the surrounding mediums on the inner and outer edges ofthe cylinder are changed.

Case 1: The temperature of the surrounding medium on the inner edge of the cylinder is greater than the corresporiding value on the outer edge of the cylinder ( 9, = 330'

K ,

St = 300" K ). The results are presented in Fig.

1.

r 105

1

05

0.5

0

{.c

-l 5

2.E=0.2

3'i=0'l

e

lime (s)

(c)

Fig. 1. Distributions of radial displacement and stess components To =2900

K, 4 =3300K, 4

=3000,K.

Case 2: The temperatures of the surrounding medium on the inner and outer edges of the cylinder are equal (

q

= .9, =3200

K

).The results are presented in Fig. 2.

0

n.2

{.1 {.o 4.8 .,|

atitBry t, r= l0cmandr= 105cm

6=0.3,r=1025cm

€=0.2, t='l025cm

x 1o!

{

(=0.3, r=1025cm

E = 0.2, r.10.25m

=0.1, r= 10.25 cm

(7)

N.D.Duc,N.T,Thuy/WUJournalofScience,Mathematics-Physics26(2010)83-92 89

r 1o'a

I l

I i I

zl

I

.l

I I

E

E=03

l. l, = 0.r

2 t-n1

tim (s)

(d)

Fig.2.Distributionsofradialdisplacementandstresscomponents

To =2900

K, 4 =

s, =3200 K'

Case 3: The temperature of the surrounding medium on the inner edge of the cylinder is smaller than the corresponding value on the outer edge of the cylinder (

4

= 30Oo

K ,

s2 --32v K )' The results are presented in Fig. 3.

100 tim€ (s)

(c)

a.titEry t, r= 10 cm and r= 10 5 cm

(=0.3,r=1025cm

C,=0:2, r=1025cm

l.g=0.1, r=1025cm 2.(=0.2, r=1025cm 3.8=0.3, r=1025cm d

.q!

(8)

90 N.D. Duc, N.T. Thuy

/

VNU Journal of Science, Mathematics - Physics 26 (2010) 83-92

(c)

Fig. 3. Diskibutions of radial displacement and stess cornponents

To=29ooK,

4

=3oooK, 9z=32ooK.

From figs.

1,2

and 3,

it

can be seen that

in

all three cases, the radial displacement and thermal

stresses vary very slowly. The displacement and stresses in the first 50 seconds vary more quickly than in the later time interval.

It

can be seen from Figs. la, 2a and 3a that the radial displacement always has possitive sign and increase slowly with time. From figs. Ld,2d and 3d

it

can be seen that the axial shess always has negative sign and

its

absolute value increases slowly

with

time. The radial and circumferential stresses

in

the cases 1 and

2

(figs.

1(b*)

and 2(b-c)) have negative sign and their absolute value increase in,the fisrt.seconds (from 0s to 3s), then decrease

in

the later time interval, with the exeption in the case 3, their histories in the fisrt 40 seconds are similar to their histories in two case above

(fig.

3b-c) but

in

the later time interval, they suddenly have possitive sign and increase slowly with time.

E

g

oo

e

E

ariitEry [,, r= l0cmand r= 10 5cm

( =0.1,r= 1025cm

l.(=0.1, 1= 1925gm 2.1=Q),1=1s25ga 3.t=0.3,1='1s2596

l.t=0.1 2 E=0'2 3.€ = 0.3

(9)

N.D. Duc, N.T. Thuy

/

VNU Journal of Science, Mathematics - Physics 26 (2010)

A3-92

91

In every case, the distribution of the displacement and sfesses at different radii are different. The radial stress at inter and outer surfaces of the cylinder

(r:

10 cm and

r =

10.5 cm) equal zero, which satisfies the given zero boundary conditons.

It

can be seen from figs. 1,

2

and 3 that the distributions of the radial displacement and stresses at

different particle's volume ratios are different. The absolute values

of

the radial displacement and stresses at

€ :0.3

are less than theirs at

I :0.1

and

( :

0.2. Therefore, when the particle's volume ratio is increased, the radial displacement and thermal stresses of the composite cylinder decrease and their histories on the time are slower.

When the temperatures of the surrounding mediums inside and outside the cylinder change, the displacement and stresses of the cylinder change. Their absolute values in the case

I

are maximum, and the corresponding values

in

the case

3

is minimum. This result satisfies practice, because the coefftcients of thermal conducfivify and heat transfer coefficient of water are much greater than the corresponding values of air. Hence, the environments inside and outside the cylinder also affect to the thermal-mechanical behavior of the cvlinder.

5.

Conclusion

Based on the goveming equations and the displacement method

in

the theory

of

elasticity, the paper determined the analytical solution

of

sfesses, deformations and displacements

for

an infinite hollow cylinder made of spherical particle filled composite material under an unsteady, axisymmetric, plane temperature field with the assumtion that the composite is elastic, homogeneous, isotropic and

the material properties are temperature -

indefendent.

o

The numerical calculations of the paper clearly analyzed the influence of time, particle's volume ratio and temperature on the states of unsteady thermal stress and displacement in the infrnite hollow cylinder made of titanium /PVC composite material.

It

can be also confirmed from the numerical results that the particle plays an important role on the states

of

stress, deformation and displacement

of

the composite cylinder. Certain volume ratios

of

particle can decrease the displacementes, strains and stresses of the composite cylinder. Hence, they can increase the crackproof capacity, waterproof capacity as well as heatproof capacity (increase the strenght)

for

composite. This

is

the basis

to

calculate and design the composite cylinder structures which are not only increased in strength, but also decreased in cost.

Acknowledgments. The results have been performed

with

the finalcial support

of

key themes QGTD 09.01 of Vietnam National University, Hanoi.

References

Y.Takeuti, Y.Tanigawa, N.Noda, T.Ochi, Transient thermal stresses in a bonded composite hollow circular cylinder under symmetrical temperature distribution, Nuclear Engineering and Design 4l (1977) 335,

Y'Takeuti, Y.Tanigawa, Axisymmetrical transient thermoelastic problems in a composite hollow circular cylinder, Nuclear Engineering and Design 45 (1978) 159.

L'S. Chen, H.S. Chu, Transient thermal stresses of a composite hollow cylinder heated by a moving line source, Computers and Structures Vol. 33, No. 5 (1989) 1205.

tll

l2l

t3l

(10)

92

N.D: Duc, N.T. Thuy

/

WU Journal of Science, Mathematics - Physics 26 (2010) 83-92

t4] K.C. Jane, Z.Y. Lee, Thermoelastic transient response of an infinitely long annular multilayered cylinder, Mechanics Research communications Yol26, No. 6 (1999) 709'

[5] K.T.S.R. Iyengar, K. Chandrashekhara, Thermal stresses in a finite hollow cylinder due to an axisymmetric temperature field at the end surface, Nuclear Engineering and Design 3 (1966) 382'

t6] K. P. Soldatos, Jian Qiao Ye, Three dimensional static, dynamic, thermo-elastic and buckling analysis of

homogeneous and lamilated composite cylinders, Composite Structures 29 (1994) 131.

[7] A. Bhattacharyya, E.J. Appiah, On the exact solution of elastoplastic response of an infinitely long composite cylinder during cyclic radial loading, Journal of Mechanics and Physics of Solids 48 (2000) I 065.

t8] S.M. Ahmed, N.A. Zeiden, Thermal stresses problem in non-homogeneous transver-sely isotropic infinite circular . cylinder, Applied Mathermatics and Compulation 133 (2002) 337.

[9] Jiann-QuoTam, Exact solution for functionally graded anisotropic cylinders subjected to thermal and mechanical loads, International Journal of Solids and Structures 38 (200 I ) 8 1 89.

t10l C.K. Chao, C.T. Chuang, R.C. Chang, Thermal stresses

in

a viscoelastic three-phase composite cylinder, Theoretical and Applied Fracture Mechanics 48 (2007) 258.

[11] K.M. Liew, S. Kitipomchai, X.Z. Zhang, C.W. Lim, Analysis of the thermal stress behaviour of functionally graded hollow curcular cylinders, Inlernational Journal of Solids and Structures 40 (2003) 2355.

tl 2] M. Jabbari, S.Sohrabpour, M.R. Eslami, Mechanical and thermal stresses in a functionally graded hollow cylinder due to radially symmetric loads, Inlernationhl Journal of Pressure Vessels and Piping 79 (2002) 493.

tl3]

Z.S. Shao, Mechanical and thermal sffesses of a functionally graded circular hollow cylinder with finite length, International Journal of Pressure Vessels and Piping 82 (2005) I 55.

[14) Z.S. Shao, G.W. Ma, Thermal-mechanical stresses in functionally graded circular hollow cylinder with linearly increasing boundary temperature, Composite Structures 83 (2008) 259.

tl5l

M. Jabbari, A. Bahtui, M. R. Eslami, Axisymmetric mechanical and thermal sffesses in thick short length FGM cylinders, International Journal ofPressure Vessels and PipingS|

(2009)296. I tl6]

T. Kong, D.X. Li, X. Wang, Thermo-magneto-dynamic stresses and perturbation of magnetic field vector in a non-

homogeneous hollow cylinder, Applied Mathermatical and Modelling 33 (2009) 2939 .

t17] M. Shariyat,

A

nonlinear Hermitian transfinite element method for ffansient behaviour analysis of hollow functionally graded cylinders with temperature-dependenr materials under thermo-mechanical loads, Inlernational Journal of Pressure Vessels and Pipin4 86 (2009) 280.

[8]

M. Shariyat, M.Khaghani, S.M.H.Lavasani, Nonlinear thermoelasticity, vibration and stress wave propagation anafyses of thick FGM cylinder with temperature-dependent material properties, European Journal of Mechanics A/Solids 29 (2010) 378.

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Dao Huy Bich, Elastic Theory, Publishers of Vietnam National University, Hanoi (2000).

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[22] Nguyen Dinh Duc, Hoang Van Tung, Do Thanh Hang, An altemative method determining the coeflicient of thermal expansion of composite material of spherical particles, Vietnam Journal of Mechanic, VAST, Vol. 29, No. | (200'7) )u.

[23] A. D. Kovalenko, Basic of Thermoelastic Theory. Kiev, Naukova Dumka 1970.

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