Consider steady heat transfer in an L-shaped solid body whose cross section is given in Figure 5-26. The thermal conductivity of the body is k = 15 W/m · °C, and heat is generated in the body at a rate of g. = 2 x 106 W/m3. The left surface of the body is insulated, and the bottom surface is maintained at a uniform temperature of 90°C. The entire top surface is subjected to convection to ambient air at Too= 25°C with a convection coefficient of h= 80 W/m2 °C, and the right surface is subjected to heat flux at a uniform rate of q''R = 5000 W/m2. The nodal network of the problem consists of 15 equally spaced nodes with Ax=Ay=1.2 cm. Five of the nodes are at the bottom surface, and thus their temperatures are known. Obtain the finite difference equations at the remaining nine nodes and determine the nodal temperatures by solving them. Convection h, To -3+34 Ay Ay 1 4 10 2 5 3 6 12! 7 13 Ax= Ay=1 8 9 ÅR 14 15 90°C -Ax+Ax+Ax+AxAx- X

Consider steady heat transfer in an L-shaped solid body whose cross section is given in Figure 5-26. The thermal conductivity of the body is k = 15 W/m · °C, and heat is generated in the body at a rate of g. = 2 x 106 W/m3. The left surface of the body is insulated, and the bottom surface is maintained at a uniform temperature of 90°C. The entire top surface is subjected to convection to ambient air at Too= 25°C with a convection coefficient of h= 80 W/m2 °C, and the right surface is subjected to heat flux at a uniform rate of q''R = 5000 W/m2. The nodal network of the problem consists of 15 equally spaced nodes with Ax=Ay=1.2 cm. Five of the nodes are at the bottom surface, and thus their temperatures are known. Obtain the finite difference equations at the remaining nine nodes and determine the nodal temperatures by solving them. Convection h, To -3+34 Ay Ay 1 4 10 2 5 3 6 12! 7 13 Ax= Ay=1 8 9 ÅR 14 15 90°C -Ax+Ax+Ax+AxAx- X

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.29P: 2.29 In a cylindrical fuel rod of a nuclear reactor, heat is generated internally according to the...

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2.29 In a cylindrical fuel rod of a nuclear reactor, heat is generated internally according to the equation where = local rate of heat generation per unit volume at r = outside radius = rate of heat generation per unit volume at the centerline Calculate the temperature drop from the centerline to the surface for a 2.5-cm-diameter rod having a thermal conductivity of if the rate of heat removal from its surface is 1.6 .
1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
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