1. a) A furnace wall is composed of 220 mm of fire brick, 150 mm of common brick, 50 mm of 85% magnesia and 3 mm of steel plate on the outside. If the inside surface temperature is 1500°C and outside surface temperature is 90°C, estimate the temperatures between layers and calculate the heat loss in kW/h.m². Given, k (for fire brick) = 4kJ/m.hr.K k (for common brick) = 2.8 kJ/m.hr.K k (for steel) = 240 kJ/m.hr.K k (for 85% magnesia) = 0.24 kJ/m.hr.K

1. a) A furnace wall is composed of 220 mm of fire brick, 150 mm of common brick, 50 mm of 85% magnesia and 3 mm of steel plate on the outside. If the inside surface temperature is 1500°C and outside surface temperature is 90°C, estimate the temperatures between layers and calculate the heat loss in kW/h.m². Given, k (for fire brick) = 4kJ/m.hr.K k (for common brick) = 2.8 kJ/m.hr.K k (for steel) = 240 kJ/m.hr.K k (for 85% magnesia) = 0.24 kJ/m.hr.K

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 8.8P

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