An aluminum pipe carries steam at 110 C. The conductivity is 185 W/mk. The pipe ID is 10 cm and the OD is 12 cm. The temperature distribution through the pipe is
In T(r) = Tᵢ + (Tₒ-Tᵢ) In(r/rᵢ)/ln(rₒ/rᵢ)
Assume the inner radius is at the steam temperature, and that the outer surface has a heat transfer coefficient of 15 W/m²K.
If Tair is 30C-what is the heat flow through pipe wall?
What is the surface temperature of the pipe?
Now add 5 cm of insulation (k = 0.20 W/mK) with an exterior heat transfer coefficient of 10 W/m²K. (Assume outer radius of pipe and inner radius of insulation are at same temperature)
What is heat flow through the pipe?
What is temperature of insulation at the interior and exterior radii?