A thin-walled container with a hot process fluid at 50°C is placed in a quiescent, cold water bath at 10°C. Heat transfer at the inner and outer surfaces of the container may be approximated by free convection from a vertical plate.
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(a) Determine the overall heat transfer coefficient between the hot process fluid and the cold water bath. Assume the properties of the hot process fluid are those of water.
(b) Generate a plot of the overall heat transfer coefficient as a function of the hot process fluid temperature Tooh for the range 20 to 60°C, with all other conditions remaining the same.