A 2-m x 1.8-m section of wall of an industrial furnace burning natural gas is not insulated, and the temperature at the outer surface of this section is measured to be 80°C. The temperature of the furnace room is 30°C, and the combined convection and radiation heat transfer coefficient at the surface of the outer furnace is 10 W/m² • °C. It is proposed to insulate this section of the furnace wall with expanded perlite insulation (k = 0.052 W/m • °C) in order to reduce the heat loss by 90%. Assuming the outer surface temperature of the metal section still remains at about 80°C, determine the thickness of the insulation that needs to be used. ANSWER:_______cm

A 2-m x 1.8-m section of wall of an industrial furnace burning natural gas is not insulated, and the temperature at the outer surface of this section is measured to be 80°C. The temperature of the furnace room is 30°C, and the combined convection and radiation heat transfer coefficient at the surface of the outer furnace is 10 W/m² • °C. It is proposed to insulate this section of the furnace wall with expanded perlite insulation (k = 0.052 W/m • °C) in order to reduce the heat loss by 90%. Assuming the outer surface temperature of the metal section still remains at about 80°C, determine the thickness of the insulation that needs to be used. ANSWER:_______cm

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 1.7P: A cooling system is to be designed for a food storage warehouse for keeping perishable foods cool...

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