b) Consider steady-state conditions for one-dimensional conduction in a plane wall having a thermal conductivity k = 50 W/mk and a thickness L = 0.25 m, with no internal heat generation. Determine i) the heat flux and the unknown quantity for each case; and ii) sketch the temperature distribution, indicating the direction of the heat flux. Case T1(°C) T2(°C) dT/dx (K/m) (W/m2) 1 50 -20 2 70 160 3 40 -80

b) Consider steady-state conditions for one-dimensional conduction in a plane wall having a thermal conductivity k = 50 W/mk and a thickness L = 0.25 m, with no internal heat generation. Determine i) the heat flux and the unknown quantity for each case; and ii) sketch the temperature distribution, indicating the direction of the heat flux. Case T1(°C) T2(°C) dT/dx (K/m) (W/m2) 1 50 -20 2 70 160 3 40 -80

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 2.4P: A plane wall 15 cm thick has a thermal conductivity given by the relation k=2.0+0.0005T[W/mK] where...

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Discuss the modes of heat transfer that determine the equilibrium temperature of the space shuttle Endeavour when it is in orbit. What happens when it reenters the earths atmosphere?
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1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm thick, for reinforcement. If the total cross-sectional area of the nails is 0.5% of the wall area, determine the unit thermal conductance of the composite wall and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 25°C. Neglect contact resistance between the wood layers.
2.15 Suppose that a pipe carrying a hot fluid with an external temperature of and outer radius is to be insulated with an insulation material of thermal conductivity k and outer radius . Show that if the convection heat transfer coefficient on the outside of the insulation is and the environmental temperature is , the addition of insulation actually increases the rate of heat loss if , and the maximum heat loss occurs when . This radius, is often called the critical radius.
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A steam pipe 200 mm in diameter passes through a large basement room. The temperature of the pipe wall is 500C, while that of the ambient air in the room is 20C. Determine the heat transfer rate by convection and radiation per unit length of steam pipe if the emissivity of the pipe surface is 0.8 and the natural convection heat transfer coefficient has been determined to be 10 W/m2K.
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