A large steel plate having a thickness of L = 4 in, thermal conductivity of k= 7.2 Btu/h·ft. °F, and an emissivity of ε = 0.7 is lying on the ground. The exposed surface of the plate at x = L is known to exchange heat by convection with the ambient air at T∞ = 90°F with an average heat transfer coefficient of h = 12 Btu/h·ft².°F as well as by radiation with the open sky with an equivalent sky temperature of Tsky =480 R. Also, the temperature of the upper surface of the plate is measured to be 80°F. Assuming steady one-dimensional heat transfer, (a) express the differential equation and the boundary conditions for heat conduction through the plate, (b) obtain a relation for the variation of temperature in the plate by solving the differential equation, and (c) determine the value of the lower surface temperature of the plate at x = 0. Tsky h, To Convection Radiation XA 80°F L E Plate 0 Ground

A large steel plate having a thickness of L = 4 in, thermal conductivity of k= 7.2 Btu/h·ft. °F, and an emissivity of ε = 0.7 is lying on the ground. The exposed surface of the plate at x = L is known to exchange heat by convection with the ambient air at T∞ = 90°F with an average heat transfer coefficient of h = 12 Btu/h·ft².°F as well as by radiation with the open sky with an equivalent sky temperature of Tsky =480 R. Also, the temperature of the upper surface of the plate is measured to be 80°F. Assuming steady one-dimensional heat transfer, (a) express the differential equation and the boundary conditions for heat conduction through the plate, (b) obtain a relation for the variation of temperature in the plate by solving the differential equation, and (c) determine the value of the lower surface temperature of the plate at x = 0. Tsky h, To Convection Radiation XA 80°F L E Plate 0 Ground

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.29P: 1.29 A spherical interplanetary probe with a 30-cm diameter contains electronic equipment that...

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1.29 A spherical interplanetary probe with a 30-cm diameter contains electronic equipment that dissipates 100 W. If the probe surface has an emissivity of 0.8, what is its surface temperature in outer space? State your assumptions in the calculations.
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