A 15'x12'x15'(LXWXH) room with temperature at 70°F dB and 50°F wB needs SA with air change rate 10 times/hr. If SA is 100% from outside air (temperature 50°F dB and 40°F wB), determine the required heating energy (MBtu) to keep the room temperature during 1/2 hours. (Average air specific heat at constant pressure is 0.24 Btu/lbm.R and density is 0.07639 lbm/ft')

A 15'x12'x15'(LXWXH) room with temperature at 70°F dB and 50°F wB needs SA with air change rate 10 times/hr. If SA is 100% from outside air (temperature 50°F dB and 40°F wB), determine the required heating energy (MBtu) to keep the room temperature during 1/2 hours. (Average air specific heat at constant pressure is 0.24 Btu/lbm.R and density is 0.07639 lbm/ft')

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.39P: The tip of a soldering iron consists of a 0.6-cm- diameter copper rod, 7.6 cm long. If the tip must...

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