9.3 In order to reduce the heat loss through a large furnace wall, the decision has been made to add external insulation. Calculate the thickness of insulation required to reduce the heat loss by 75%. Before the change is made, no outer steel shell is used. Data: Refractory brick and wall brick: k=0.87 W m¹ K₁¹. Inside Purnace Insulation Insulation: = 0.090 W m¹¹ K¹¹. Steel: k= 43 W m¹ K¹. h 55 W m K (inside furnace). h 11 W m K (outside furnace). Refractory Brick, 250 mm 8-698- Wall Brick, 50 mm Outer Steel Shell, 25 mm

9.3 In order to reduce the heat loss through a large furnace wall, the decision has been made to add external insulation. Calculate the thickness of insulation required to reduce the heat loss by 75%. Before the change is made, no outer steel shell is used. Data: Refractory brick and wall brick: k=0.87 W m¹ K₁¹. Inside Purnace Insulation Insulation: = 0.090 W m¹¹ K¹¹. Steel: k= 43 W m¹ K¹. h 55 W m K (inside furnace). h 11 W m K (outside furnace). Refractory Brick, 250 mm 8-698- Wall Brick, 50 mm Outer Steel Shell, 25 mm

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.38P

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