Thermal Stresses in Semi-Infinite Solid Rectangular Plate with Heat Source

DOI : 10.17577/IJERTV2IS70634

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Thermal Stresses in Semi-Infinite Solid Rectangular Plate with Heat Source

C. M. Jadhav

Department of Mathematics, Dadasaheb Rawal College Dondaicha, NMU Jalgaon University, Jalgaon [M.S.], INDIA

This paper is concerned with three dimensional inverse thermoelastic problem of semi-infinite solid rectangular plate due to internal heat source. To determine unknown temperature distribution, displacement and thermal stresses on edge z=h of the rectangular plate due to internal heat sources with known third kind boundary and initial condition by applying Fourier and Laplace transform technique.

The results are obtained in terms of infinite series and

Consider a solid rectangular plate from fig. 1 occupying the space D: 0 x < , 0 y < , 0 z h.The displacement components ux, uy, uz in the x, y, z direction respectively are in the integral form as in [1] u = 1 2U + 2 U 2U + T dx (2.1)

x 0 E y2 z2 x2

x 0 E y2 z2 x2

y 0 E z2 x2 y2

y 0 E z2 x2 y2

u = 1 2U + 2U 2U + T dy (2.2)

u = h 1 2U + 2U 2U + T dz (2.3)

z 0 E x2 y2 z2

the numerical calculations are carried out by using MATHCAD -7 software and shown graphically.

Keywords: Three dimensional inverse thermoelastic problem, solid rectangular plate, integral transform.

  1. Introduction

    Many heat conduction problem encountered in engineering application involve time as independent variable. The goal of analysis is to determine the variation in temperature displacement and stresses with known boundary condition. Tanigawa et al. [1] have studied thermal stress analysis of a rectangular plate and its thermal stress intensity factor for compressive

    stress field. Khobragade et al. [4] to determine an

    where E, and are the Young modulus, the poisson ratio and the linear coefficient of thermal

    expansion of the material of the plate respectively, U(x, y, z ,t) is the Airy stress function which satisfies the differential equation.

    2 2 2

    2 2 2

    2 + 2 + 2 2 U x, y, z, t =

    x y z

    2 2 2

    2 2 2

    E 2 + 2 + 2 T(x, y, z, t) (2.4)

    x y z

    Here T(x, y, z, t) denotes the temperature of the thin rectangular plate satisfying the following differential equation.

    inverse unsteady-state thermoelastic problem of thick

    2T + 2 T + 2T + (x,y,z,t) = 1 T

    (2.5)

    rectangular plate. Lamba et al. [9] have studied thermoelastic problem of thin rectangular plate due to partially distributed heat supply. Himanshu S.Roy and N.W.Khobragade have discussed transient thermoelastic problem of infinite rectangular slab with second kind boundary condition.

    In the present paper, an attempt has been made

    x2 y2 z2 k t

    Where k is thermal conductivity and is the thermal diffusivity of the material of the plate and (x, y, z, t) is heat generated within the rectangular plate for t>0 subject to initial conditions

    T x, y, z, 0 = 0 (2.6)

    The boundary conditions

    completely the inverse unsteady state thermoelastic

    T(x,y,z,t)

    = F1 y, z, t (2.7)

    problem of semi-infinite solid rectangular plate with

    x x=0

    internal heat source applied for upper plane surface

    T(x,y,z,t)

    y y=0

    = F2 x, z, t (2.8)

    with third kind boundary conditions. To determine the

    temperature, displacement and thermal stresses on the

    T(x, y, z, t) + c T(x,y,z,t)

    z

    z=0

    = 0 (2.9)

    edge z= h of semi- infinite rectangular plate due to internal heat by applying Fourier and Laplace transform

    T(x, y, z, t) z=h = g x, y, t Unknown) (2.10) The interior condition

    technique.

  2. Statement of the problem

    T(x, y, z, t) + c T(x,y,z,t)

    z

    z=

    = f x, y, t (Known)

    (2.11)

    The components in term of U(x, y, z, t) are given by

    = 2U + 2U (2.12)

    where p = l

    xx y2

    z2

    = 2U + 2U (2.13)

    g x, y, t =

    K , x K , y 2k

    yy z2

    x2

    ,=0 2

    = 2U + 2U (2.14)

    1 l+1

    l sin ph cp cos ph

    zz x2

    y2

    l=1 1c2p2

    the equations (2.1) to (2.14) constitute the

    t f , , t PI

    mathematical formulation of the problem under consideration.

  3. Solution of the problem

    The Fourier integral transform of f(x), 0 x < is

    0

    c dPI

    dz

    z=

    z=

    e 2+2 +p2 tt dt dd

    K , x K , y 2k

    defined to be

    ,=0 2

    F = K , x F(x)dx

    (3.1)

    1 l+1

    l sin p h cp cos p h

    x=0

    then inverse formula

    l=1 1c2p2

    F x = K , x F d (3.2) ×

    =0

    t PI

    c dPI

    e 2+2+p2 tt dt

    Where K , x = 2 cos x

    (3.3)

    0

    +

    +

    dd

    z=0

    dz z=0

    By applying the Fourier transform two times and

    ,=0

    K , x K , y L1 PI

    Laplace transform to equation (2.5) and their inverses, we obtain

    2

    2

    d2 T p2 T = + (3.4)

    dz k

    Where p2 = 2 + 2 + s , = +

    t e 2 +2 +p2 tt dt dd (3.10)

    0

    0

    where

    1 z = sin pz cp cos pz

    1 2

    t =

    1 = K(, x) x=0 F1 , 2 = K(, y) y=0 F2 , upper limit vanishes

    dT ,,z,t

    1

    0

    0

    t f , , t PI z=

    T , , z, t + c

    dz

    z=0

    = 0 (3.5)

    c dPI

    dz

    z=

    e 2+2 +p2 tt dt

    T , , z, t z=h = g , , z, t (3.6)

    dT ,,z,t

    2 z = sin p z cp cos p z

    T , , z, t + c

    dz

    z=

    = f , , t

    2 t =

    t PI

    c dPI

    e 2+2+p2 tt dt

    (3.7)

    The equation (3.4) is a second order differential

    0 z=0

    dz z=0

    equation whose solution is in form

    t = t

    e 2 +2 +p2 tt dt

    0

    0

    3

    T = Aepz + Bepz + PI (3.8)

    (Q )

    2 2

    2 2

    Where PI = k

    D p

    , D d

    dz

    and A, B are

  4. Determination of the airy stress function

    Substituting the value of T(x, y, z, t) from equation

    constant. Using equation (3.5), (3.7) in (3.8) we obtain the values of A and B substituting these

    (3.9) in the equation (2.4), one obtains

    values (3.8) and then apply inverse of Laplace transform and Fourier integral transform. We

    U x, y, z, t = E

    K , x K , y 2k

    2

    2

    obtain

    ,=0

    ,=0

    T x, y, z, t =

    K , x K , y 2k

    2

    2

    0

    0

    1 l+1

    ,=0

    ,=0

    l=1 p2 1c2p2

    l sin pz cp cos pz

    1

    1

    l+1

    1 1c2p2 l sin pz cp cos pz

    t f , , t PI z=

    l=

    t f , , t PI

    c dPI

    +E

    +E

    dz

    z=

    e 2+2 +p2 tt dt dd

    0

    c dPI

    z=

    e 2+2+p2 tt dt dd

    ,=0

    K , x K , y 2k

    2

    2

    dz z=

    1 l+1

    l sin p z cp cos p z

    ,=0

    K , x K , y 2k

    2

    2

    l=1 p2 1c2p2

    ×

    1 l+1

    l=1 1c2p2 l sin p z cp cos p z

    t PI

    c PI

    e 2+2+p2 tt dt

    0

    × dd

    z=0

    dz z=0

    t PI

    c dPI

    e 2+2+p2 tt dt

    E

    K , x K , y L1 PI

    0 z=0

    dz z=0

    =0

    ,=0

    ,=0

    dd + K , x K , y L1 PI

    t e 2 +2+p2 tt dt dd (3.9)

    t e 2 +2+p2 tt dt dd (4.1)

    0

    0

    U x, y, z, t =

    E

    E

    0

    ,=0

    K , x K , y 2k

    2

    2

    1 l+1

    2k

    1 l+1

    l z t z t

    p2 1c2p2

    dd

    2

    l=1 p2 1c2p2 1 1 2 2

    l=1 l 1 z 1 t 2 z 2 t

    + y=0 =0 K" , y d dy

    K , x d L1 PI 3 t

    E

    K , x K , y L1 PI t dd

    =0

    =0

    3 + K , y d dy K , x d

    y=0

    =0

    =0

    (4.2)

    2k

    1 l+1

    l z t z t

  5. Determination of the displacement

    2

    l=1 p2 1c2 p2 1 1 2 2

    components

    +

    +

    y=0 =0

    K , y d dy

    Substituting the value of U(x, y, z, t) from equation

    K , x d L1 PI 3 t (5.2)

    (4.1) in the equation (2.1), (2.2), (2.3) one obtains

    =0

    2k

    ux =

    K , x d dx

    K" , y d

    uz = K , y d K" , x d

    x=0 =0

    =0

    =0

    =0 2

    2k

    1 l+1

    l z t z t

    1 l+1

    2

    l=1 p2 1c2 p2 1 1 2 2

    p2 1c2 p2

    1 h h

    K , x d dx

    l= l 1 z dz 1 t 2 z dz 2 t

    x=0 =0 0 0

    =0

    K" , y d L1 PI 3 t

    x=0

    =0

    K , x d dx

    K , y d

    =0

    =0

    =0

    K , y d

    K" , x d

    2k

    =0

    =0

    1 l+1

    l " z t " z t

    h L1 PI dz 3 t

    2

    l=1 p2 1c2p2 1 1 2 2

    0

    2k

    2 L1 PI

    =0 K , x d =0 K" , y d 2

    x=0 =0 K , x d dx K n , y 3 t

    z2

    1 l+1

    p2 1c2 p2

    +

    K" , x d dx

    l=1 l h z dz t h z dz t

    x=0

    =0

    0 1 1 0 2 2

    =0

    K , y d 2k

    2

    2

    1 l+1

    l z t z t

    K , x d

    K" , y d h L1 PI dz 3 t

    l=1 p2 1c2 p2 1 1 2 2

    =0

    =0 0

    +

    K" , x d dx

    +

    K , x d K , y d 2k

    x=0

    =0

    =0

    =0 2

    =0 K , y d L1 PI 3 t

    1 l+1

    + K , x d dx

    K , y d

    p2 1c2 p2

    x=0

    =0

    =0

    l=1 l h "1 z dz 1 t h "2 z dz 2 t

    2k

    1 l+1

    l z t z t 0 0

    2

    l=1 p2 1c2 p2 1 1 2 2

    +

    K , x d

    K , y d

    =0

    =0

    + x=0 =0 K , x d dx =0 K , y d

    h L1 PI dz 3 t

    0

    0

    L1 PI 3 t (5.1)

    2k

    uy =

    K , y d dy

    K , x d

    + K , x d K , y d 2

    2k

    y=0

    =0

    1 l+1

    p2 1c2p2

    =0

    =0

    =0

    1 l+1

    p2 1c2p2

    2 l=1 l "1 z 1 t "2 z 2 t

    l=1 l h z dz t h z dz t

    K , y d dy K , x d

    0 1 1 0 2 2

    y=0

    2 L1 PI

    z2

    =0

    3 t

    =0

    + K , x K , y h L1

    m,n=1 m n 0

    m,n=1 m n 0

    (5.3)

    y=0

    =0

    K , y d dy

    K" , x d

  6. Determination of stress functions

    Using (4.1) in (3.14), (3.15) and (3.16) the stress

    2k

    =0

    =0

    1 l+1

    l z t z t

    functions are obtained as

    2

    l=1 p2 1c2p2 1 1 2 2

    xx = E K , x d K" , y d

    K , y d dy

    K" , x d

    =0

    1 l+1

    =0

    y=0 =0

    =0

    =0

    L1

    =0

    2k

    p2 1c2p2

    PI

    3 t

    2 l=1 l 1 z 1 t 2 z 2 t

    y=0

    y=0

    +

    =0

    K" , y d dy

    K , x d

    E

    K , x d

    K" , y d

    e p2 +A t

    1

    =0

    =0

    2

    z0 x y

    L PI 3 t

    1 e e

    erf erf

    4 4

    =0

    =0

    =0

    =0

    E K , x d

    K , y d 2k

    2

    2

    ×

    ×

    1 l+1

    8

    1 l+1

    l sin p z cp cos p z

    l=

    l=

    1 p2 1c2p2 l "1 z 1 t "2 z 2 t

    2 l=1 1c2 p2

    =0

    =0

    E

    K , x d

    K , y d

    e p2+B t

    2 L1 PI

    t (6.1) 1

    x y 2

    =0

    =0

    z2 3

    + 2 e(zz0)erf erf e p +1 t

    2k

    1p

    4

    2

    4

    (7.6)

    yy = E K , x d K , y d

    g x, y, t = 1 e ez0 erf x

    erf y

    1 l+1

    =0

    =0 2

    8 1 l+1

    4

    4

    l=

    l=

    1 p2 1c2p2 l "1 z 1 t "2 z 2 t

    =0

    =0

    =0

    =0

    E K , x d K , y d

    × 2 1 c2p2 l sin ph cp cos ph

    l=1

    e p2 +A t

    2 L1 PI

    z2

    3 t

    1 e 2ez0 erf x

    4

    erf y

    4

    =0

    =0

    E

    K" , x d

    K , y d 2k

    2

    2

    × 8

    =0

    =0

    1 l+1

    1c2p2

    1 l+1

    l z t z t

    2

    l=1 l sin p h cp cos p h

    l=1 p2 1c2p2 1 1 2 2

    =0

    =0

    E

    L1 PI t

    K" , x d

    K , y d

    e p2+B t

    + 1 e(hz0)erf x erf y e p2 +1 t

    =0

    =0

    3 (6.2)

    1p2

    4

    4

    2k

    (7.7)

    zz = E K" , x d K , y d 2

    8. Numerical results

    =0 =0

    1 l+1

    l z t z t

    For Aluminum metal

    l=1 p2 1c2p2 1 1 2 2

    Modulus elasticity E = 6.9 × 1011 Poisson

    =0

    =0

    E

    L1 PI 3 t

    E

    K" , x d

    =0

    =0

    K , x d

    K , y d

    K" , y d 2k

    ratio = 0.35, = 12.84 × 106

    Thermal Expansion coefficient t = 25.5 × 106

    Thermal Diffusivity k=117, c=1

    Thermal Conductivity = 3.33 , h=1, = 0.5

    =0

    0

    0

    =0 2 l

    1 l+1

    l z t z t

    A=3, B=2, p= , x=2, y=3, z = 0.2

    l=1 p2 1c2p2 1 1 2 2

    =0

    =0

    E

    L1 PI t

    K , x d

    K" , y d

    T x, y, z, t =

    1 e0.5 2e0.50.2erf 2 erf 3

    =0

    =0

    3 (6.3)

    4

    4

    7. Special case

    1 l+1

    l sin l z l cos l z

    Setting

    × 8

    l 2

    f x, y, t = x y (1 e )2et (7.1)

    2

    l=1 1

    x, y, z, t = x y e(zz0)et

    l 2+3 t

    > 0

    (7.2)

    e

    f = 2

    cos x 2

    cos y (1 e )2et (7.3)

    1 e0.5 2e0.2erf 2

    4

    erf 3

    4

    1 l+1

    = 2 cos x 2 cos y e(zz0 ) 1

    (7.4)

    2

    2

    1 l

    s+

    × 8

    2

    l=1

    l sin l z l cos p z

    1 2 2

    (zz )

    t

    =1p2 cos x cosy e 0 e (7.5)

    l 2

    Substitute the values in the equation (3.9),(3.10), (4.1),(5.1),(5.2)(5.3),(6.1),(6.2)and(6.3)one obtains

    +2 t

    e

    l 2+1 t

    T x, y, z, t =

    1 e 2ez0 erf x

    erf y

    + 1

    1 l 2

    e(z0.2)erf 2

    4

    erf 3 e

    4

    (7.8)

    4

    8 1 l+1

    4

    g x, y, t =

    × 2 1 c2p2 l sin pz cp cos pz

    1 e0.5 2e0.50.2erf 2 erf 3

    l=1

    4

    4

    1 l+1

    l sin l l cos l

    × 8

    l 2

    2

    l=1 1

    l 2+3 t

    e

    1 e0.5 2e0.2erf 2

    4

    erf 3

    4

    ×

    8

    1 l+1

    1 l 2

    2

    l=1

    l sin l h l cp cos l h

    l 2+2 t

    e

    + 1 e h0.2 erf 2

    erf 3

    1 l 2

    4

    4

    l 2+1 t

    e

    (7.9)

    U x, y, t

    = E 1 e0.5 2e0.50.2erf 2

    4

    erf 3

    4

    1 l+1

    l 2 1 l 2

    × 8

    2

    l=1

    l sin l l cos l

    l 2+3 t

    e

    E 1 e0.5 2e0.2erf 2

    4

    erf 3

    4

    ×

    1 l+1

    l 2 1 l 2

    8

    2

    l=1

    l sin l h l cp cos l h

    l 2+2 t

    e

    +E 1

    e h0.2 erf 2

    erf 3

    1 l 2

    4

    4

    l 2+1 t

    e

    (7.10)

  7. Conclusion

In this paper, we discussed completely the inverse unsteady state thermoelastic problem of semi- infinite solid rectangular plate with internal heat source applied for upper plane surface with known third kind boundary and initial condition. The Fourier and Laplace integral transforms are used to obtain the numerical results. The temperature, Displacement and thermal stresses that are obtained can be applied to the design of useful structure or machines in engineering application. Any particular case of special interest can be derived by assigning suitable value of the parameters and function in the expression.

Acknowledgements

The author expresses their sincere thanks to Dr. B.R.Ahirrao for their expert comments.

References

  1. Y. Tanigawa and Komatsubara, Thermal stress analysis of a rectangular plate and its thermal stress intensity factor for compressive stress field, Journal of thermal stresses, Vol.20 (1997), pp517-542

  2. V. M. Vihak Yuzvyzk and Yasinskij A.V., The solution of plane thermoelastic problem due to diametrical compression, Int. J. Latest Trend Math

    .Vol.1 No.1 pp13-17, 2011

  3. P.C.Wankhede and N. W. Khobragade , An inverse steady-state thermoelastic problem of thin rectangular plate, Bulletin of the Calcutta mathematical society (2002)

  4. N.K.Lamba and Khobragade N.W., Thermoelastic problem of thin rectangular plate due to partially distributed heat supply, Int. Journal of Applied mathematics and mecha.8 (1): xx, 2012

  5. Himanshu S.Roy and N.W.Khobragade, Transient thermoelastic problem of infinite rectangular slab, Int.

    J. latest Trend Math .Vol.2 No.1 pp1-3, 2012

  6. Ozisik N.M., Boundary Value Problem of Heat Conduction International Textbook Company Scranton, Pennsylvania, 1968.

  7. Sneddon I.N.(1951),Fourier transform Mc Graw Hill book Co. Inc. chapter 3

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