An aluminum alloy (2024) plate, heated to a uniform temperature of Ti = 231°C, is allowed to cool while vertically suspended in a room where the ambient air and surroundings are both at 28°C. The plate is 0.4 m square with a thickness of 17 mm and an emissivity of 0.31. (a) Develop an expression for the time rate of change of the plate temperature, assuming the temperature to be uniform at any time. (b)Determine the initial rate of cooling (K/s) when the plate temperature is Ti °C.

An aluminum alloy (2024) plate, heated to a uniform temperature of Ti = 231°C, is allowed to cool while vertically suspended in a room where the ambient air and surroundings are both at 28°C. The plate is 0.4 m square with a thickness of 17 mm and an emissivity of 0.31. (a) Develop an expression for the time rate of change of the plate temperature, assuming the temperature to be uniform at any time. (b)Determine the initial rate of cooling (K/s) when the plate temperature is Ti °C.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.26P

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