A rectangular aliminium bar 0.06 m by 0.03 m [k=200 W/(mK), Cp=890 J/(kgK), g=2700 kg/m³,a=8.4x10$m²/s] is initially at a uniform temperature T= 200 °C, suddenly all four surfaces of the road are subjected to convective cooling with a heat transfer coefficient h=200 W/(m²K) into an ambient at T = 27 °C. Determine the center temperature To of the bar at t-60 s after the start of the cooling t >0 h = 200 W/m²K T, = 27 °C T, = 27 °C h = 200 W /m²K T, = 27 °C h = 200 W/m²K t>0 0.03 m T = 27 °C, t = 0 t >0 0.06 m T, = 27 °C h = 200 W/m²K t>0

A rectangular aliminium bar 0.06 m by 0.03 m [k=200 W/(mK), Cp=890 J/(kgK), g=2700 kg/m³,a=8.4x10$m²/s] is initially at a uniform temperature T= 200 °C, suddenly all four surfaces of the road are subjected to convective cooling with a heat transfer coefficient h=200 W/(m²K) into an ambient at T = 27 °C. Determine the center temperature To of the bar at t-60 s after the start of the cooling t >0 h = 200 W/m²K T, = 27 °C T, = 27 °C h = 200 W /m²K T, = 27 °C h = 200 W/m²K t>0 0.03 m T = 27 °C, t = 0 t >0 0.06 m T, = 27 °C h = 200 W/m²K t>0

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.36P

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