2. The internal diameter of a boiler generating tube is 4in. and the wall thickness is 0.375 in. In operation the external surface film temperature is 26 Btu/hr.ft2.°F, the internal film coefficient is 1700 Btu/hr.ft². °F and a 0.375 in. thickness scale having a conductivity of 0.6 Btu/hr.ft. °F is deposited on the inner surface of the tube. The metal conductivity is 26 Btu/hr.ft. °F, the furnace gas temperature is 2100 °F and the temperature of the water is 500 °F, calculate (a) the overall coefficient of heat transfer for the clean tube, (b) the overall heat transfer coefficient including the effect of the scale, (c) the

2. The internal diameter of a boiler generating tube is 4in. and the wall thickness is 0.375 in. In operation the external surface film temperature is 26 Btu/hr.ft2.°F, the internal film coefficient is 1700 Btu/hr.ft². °F and a 0.375 in. thickness scale having a conductivity of 0.6 Btu/hr.ft. °F is deposited on the inner surface of the tube. The metal conductivity is 26 Btu/hr.ft. °F, the furnace gas temperature is 2100 °F and the temperature of the water is 500 °F, calculate (a) the overall coefficient of heat transfer for the clean tube, (b) the overall heat transfer coefficient including the effect of the scale, (c) the

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 8.38P

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