Question

1. A cylindrical pipe of 1.5 m outer diameter and 5 m length has a 6.35-mm-thick aluminum alloy (2024) wall.A 100-mm-thick foam insulation (k = 1 W/Km’) is added on the outside of the pipe. The adhesive interface between the insulation and the metallic pipe wall is characterized by a thermal contact resistance of R";c = 3.5 x104 m°K/W. Estimate the steady-state cooling capacity in W required of the pipe flow, to maintain inside surface temperature of –6°C if the ambient temperature is 30 °C. The heat transfer coefficient with the ambient is h = 20 W/mK.

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