The inside surface of an insulation layer is maintained at 350°C and the outside surface dissipates heat by convection and radiation to air and wall, respectively. The temperatures of air and wall are 15 °C. The insulation layer has a thickness of 10 cm and a thermal conductivity of 15 W/m.K. What is the value of the heat transfer coefficient at the outside surface of the layer, if the temperature at the outside surface should not exceed 225 °C? (The emissivity and the width of the surface are 0.3 and 1 m., respectively. o=5.67x10-8 W/m²K*). Tw=15° T=225°C e=0.3 ТЬ3350°C T=15°C h.=? + 10 cm

The inside surface of an insulation layer is maintained at 350°C and the outside surface dissipates heat by convection and radiation to air and wall, respectively. The temperatures of air and wall are 15 °C. The insulation layer has a thickness of 10 cm and a thermal conductivity of 15 W/m.K. What is the value of the heat transfer coefficient at the outside surface of the layer, if the temperature at the outside surface should not exceed 225 °C? (The emissivity and the width of the surface are 0.3 and 1 m., respectively. o=5.67x10-8 W/m²K*). Tw=15° T=225°C e=0.3 ТЬ3350°C T=15°C h.=? + 10 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 1.1P: 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed...

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