A newly cast polymer sheet is laid down on a moving conveyer belt to cool. A side view of the process is shown below. The polymer sheet measures 2 m by 1.5 m and is 1.5 mm thick. Because the conveyer belt is an open mesh, both sides of the polymer sheet are assumed to be uniformly exposed to air. The conveyer belt moves at a linear velocity of 0.5 m/s. The bulk temperature of the surrounding air is constant at 27°C. At one location in the process, the surface temperature of the polymer sheet (both top and bottom surfaces) is 107°C. The thermal conductivity of the solid polymer at 107°C is 0.12 W/m · K.
a. What is the film temperature for the cooling process?
b. What is the total heat-transfer rate (in Watts) from the polymer sheet at the point in the process when the surface temperature of the polymer sheet is 107°C?

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Tm = 27°C Ts = 107°C 0.5 m/sec conveyer 2.0 m = 27°C 00