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The steel pipe (100 mm outer diameter) is covered with two layers of insulation. The 40...

The steel pipe (100 mm outer diameter) is covered with two layers of insulation. The 40 mm thick inner layer has a thermal conductivity of 0.07 W / (mK). Outer layer, 20 mm thick has a thermal conductivity of 0.15 W / (m K). The pipe is used to drain 500 kPa pressurized steam. The temperature on the outer insulation surface is 24 ° C. If the pipe is 8 m long, determine the following: (assuming that the conduction heat transfer resistance of steel pipes and vapor convection resistance is ignored).
a. Heat loss per hour. = kJ / hour.
b. Temperature between insulation layers. = ° C.

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