Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 250 ° C. The plates are 70 cm x 40 cm in dimensions and 2.5 cm thick. The convection heat transfer coefficient on the upper surface is 20 W / (m² ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = Answer kJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss occurring = Answer kJ.

Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 250 ° C. The plates are 70 cm x 40 cm in dimensions and 2.5 cm thick. The convection heat transfer coefficient on the upper surface is 20 W / (m² ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = Answer kJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss occurring = Answer kJ.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.49P

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