2. (8.17) A flat-plate solar collector is used to heat atmospheric air flowing through a rectangular channel. The bottom surface of the channel is well insulated, while the top surface is subjected to a uniform heat flux (see figure in text). a. Beginning with an appropriate differential control volume, obtain an equation that could be used to determine the mean air temperature Tm(x) as a function of distance along the channel. Solve this equation to obtain an expression for the mean temperature of the air leaving the collector. b. With air inlet conditions of mdot=0.1 kg/s and Tm,i=40°C, what is the air outlet temperature if L=3m, w=1m, and qo”=700 W/m²? The specific heat of air is 1008J/kg K. (Ans: Tm,o=60.8°C)

2. (8.17) A flat-plate solar collector is used to heat atmospheric air flowing through a rectangular channel. The bottom surface of the channel is well insulated, while the top surface is subjected to a uniform heat flux (see figure in text). a. Beginning with an appropriate differential control volume, obtain an equation that could be used to determine the mean air temperature Tm(x) as a function of distance along the channel. Solve this equation to obtain an expression for the mean temperature of the air leaving the collector. b. With air inlet conditions of mdot=0.1 kg/s and Tm,i=40°C, what is the air outlet temperature if L=3m, w=1m, and qo”=700 W/m²? The specific heat of air is 1008J/kg K. (Ans: Tm,o=60.8°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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.48P

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