A hot silver plate is having its upper surface cooled by air forced convection of 15...

A hot silver plate is having its upper surface cooled by air forced convection of 15 °C with heat transfer coefficient of 220 W/m.K. The 10-cm thick plate (mass density ρ=8530 kg/m3, Cp=380J/kg.K, k=110 W/m.K, and α=33.9×10-6 m2/s) has a uniform initial temperature of 650 °C, and the bottom surface of the plate is insulated.

(a) calculate the Bi number and determine whether the lumped capacitance method can be used. (2 points)

(b) Determine the temperature at the center plane of the plate after 3 minutes of cooling. Solve this problem using the analytical one-term approximation method. (Hint: use table 5.1 in the lecture slides) (8 points)

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samet mamat answered 8 months ago

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