Task 3 Air at atmospheric pressure and a mean temperature of 327ºC flows through a steel pipe of internal diameter 100 mm and external diameter 120 mm as shown in figure 1. The ambient temperature is 20ºC. (a) Determine the rate of heat loss per meter length of pipe. (i) when uninsulated. (ii) when insulated with 50mm of insulator. (b) Calculate the surface temperature of the insulation. Thermal conductivity of steel ks = 45 W/(m K) Thermal conductivity of insulation k= 1.15 W/(mK) Inner convective heat transfer coefficient for steel h; = 14.27 W/(m²K) Outer convective heat transfer coefficient for steel hos= 15 W/(m²K) Outer convective heat transfer coefficient for insulation hoi = 9 W/(m² k) hoi k₁ 13 0₁-327°C h₁ r₁-50mm r₂ 60mm Mos OR=20°C

Task 3 Air at atmospheric pressure and a mean temperature of 327ºC flows through a steel pipe of internal diameter 100 mm and external diameter 120 mm as shown in figure 1. The ambient temperature is 20ºC. (a) Determine the rate of heat loss per meter length of pipe. (i) when uninsulated. (ii) when insulated with 50mm of insulator. (b) Calculate the surface temperature of the insulation. Thermal conductivity of steel ks = 45 W/(m K) Thermal conductivity of insulation k= 1.15 W/(mK) Inner convective heat transfer coefficient for steel h; = 14.27 W/(m²K) Outer convective heat transfer coefficient for steel hos= 15 W/(m²K) Outer convective heat transfer coefficient for insulation hoi = 9 W/(m² k) hoi k₁ 13 0₁-327°C h₁ r₁-50mm r₂ 60mm Mos OR=20°C

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.37P

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