Transpiration cooling in a planar system. Two large flat porous horizontal plates are sepa- rated by a relatively small distance L. The upper plate at y = L is at temperature T₁, and the lower one at y = 0 is to be maintained at a lower temperature To. To reduce the amount of heat that must be removed from the lower plate, an ideal gas at To is blown upward through both plates at a steady rate. Develop an expression for the temperature distribution and the amount of heat qo that must be removed from the cold plate per unit area as a function of the fluid properties and gas flow rate. Use the abbreviation = pCpv,L/k. T-TL ey/L - e Answer: ; k(T₁ - To L To-T 1 -90=

Transpiration cooling in a planar system. Two large flat porous horizontal plates are sepa- rated by a relatively small distance L. The upper plate at y = L is at temperature T₁, and the lower one at y = 0 is to be maintained at a lower temperature To. To reduce the amount of heat that must be removed from the lower plate, an ideal gas at To is blown upward through both plates at a steady rate. Develop an expression for the temperature distribution and the amount of heat qo that must be removed from the cold plate per unit area as a function of the fluid properties and gas flow rate. Use the abbreviation = pCpv,L/k. T-TL ey/L - e Answer: ; k(T₁ - To L To-T 1 -90=

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.3P

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