1. A composite furnace wall is made up of a 12-in. lining of magnesite refractory brick, a 5-in. thickness of 85% magnesia, and a steel casing 0.10-in. thick. Flue gas temperature is 2200 F and the boiler room is at 80 F. Gas side film coefficient is 15 Btu/hr-sq.ft-F and air side is 4.0. Determine: a. The thermal current Q/A b. Interface temperatures c. Effect on thermal current and inside refractory wall temperature if the magnesia insulation were doubled.

1. A composite furnace wall is made up of a 12-in. lining of magnesite refractory brick, a 5-in. thickness of 85% magnesia, and a steel casing 0.10-in. thick. Flue gas temperature is 2200 F and the boiler room is at 80 F. Gas side film coefficient is 15 Btu/hr-sq.ft-F and air side is 4.0. Determine: a. The thermal current Q/A b. Interface temperatures c. Effect on thermal current and inside refractory wall temperature if the magnesia insulation were doubled.

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 8.59P

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