The composite plate as shown in the figure consists of a foam insulation squeezed between two aluminum alloy panels. The length and the width of the plate are L-10 m and W-3.5 m respectively. If the inner (bottom) surface of the plate is kept at -10°C and outer (top) surface is exposed to air flow at 32°C and 105 km/h, and the solar irradiation. a) For equivalent values of the solar absorptivity and the emissivity of the outer surface (a-e-0.5) estimate the average temperature of the outer surface, (T,.) b) What is the total heat transfer c) What would be the average temperature of the outer surface (T,6) if a=0.15 and e=0,8? qš = 750 W/m² qöonv E 4 = 105 km/h T = 32°C Tso, E=as = 0.5 W = 3,5m %3D ty = 5 mm Urethane foam k = 0.026 W/m-K goond t2 = 50 mm t3 = 5 mm Aluminum alloy kp = 180 W/m-K Ts =-10°C

The composite plate as shown in the figure consists of a foam insulation squeezed between two aluminum alloy panels. The length and the width of the plate are L-10 m and W-3.5 m respectively. If the inner (bottom) surface of the plate is kept at -10°C and outer (top) surface is exposed to air flow at 32°C and 105 km/h, and the solar irradiation. a) For equivalent values of the solar absorptivity and the emissivity of the outer surface (a-e-0.5) estimate the average temperature of the outer surface, (T,.) b) What is the total heat transfer c) What would be the average temperature of the outer surface (T,6) if a=0.15 and e=0,8? qš = 750 W/m² qöonv E 4 = 105 km/h T = 32°C Tso, E=as = 0.5 W = 3,5m %3D ty = 5 mm Urethane foam k = 0.026 W/m-K goond t2 = 50 mm t3 = 5 mm Aluminum alloy kp = 180 W/m-K Ts =-10°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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.48P

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