A 2.5-cm-OD, 2-cm-ID copper pipe carriers liquid oxygen to the storage site of a space shuttle at ??183?C and 0.04 m3/min. The ambient air is at 21?C and has a dew point of 10?C. How much insulation with a thermal conductivity of 0.02 W/(m K) is needed to prevent condensation on the exterior of the insulation if hc + hr = 17 W/(m2 K) on the outside?GIVENInsulated copper pipe carrying liquid oxygenInside diameter (Di) = 2 cm = 0.02 mOutside diameter (Do) = 2.5 cm = 0.025 mLOX temperature (Tox) = ?? 183?CLOX flow rate (mox) = 0.04 m3/minThermal conductivity of insulation (ki) = 0.02 W/(m K)Exterior heat transfer coefficients (ho = hc + hr) = 17 W/(m2 K)Ambient air temperature (T??) = 21?CAmbient air dew point (Tdp) = 10?CASSUMPTIONSSteady-state conditions have been reachedThe thermal conductivity of the insulation does not vary appreciably with temperatureRadial conduction onlyThe thermal resistance between the inner surface of the pipe and the liquid oxygen is negligible, therefore Twi =Tox

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D,= 0.02 m T- 10°C D. = 0.025 m Lax -183°C Two Tox=C D, Tw -Copper Plpe Insulation