Determine the overall heat transfer coefficient U

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Reference no: EM13720683

A deep freezer for hazardous chemicals is to be maintained at -20oF to insure a safe environment for the chemicals. The freezer is in a room that is kept at 60oF, and the inner and outer walls of the freezer are made of 26-gauge (0.0184-in) steel. The insulation in the walls of the freezer is 2 inches of unpacked glass wool, and the convective heat-transfer coefficients are: ho = 4 Btu/h ft2 oF and hi = 2 Btu/h ft2 oF.

1) Determine the overall heat transfer coefficient U.

2) What is the heat-transfer rate (W) from the room into the freezer?

Reference no: EM13720683

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