Exercise 1.17 A pipe with a diameter of 10 cm is surrounded by a sheet-metal clad insulation of 20 cm mineral wool (A = 0,045 W/m K). a) What is the heat loss per meter of pipe when the pipe is 9...

Question

Question

Answer 1

Answer #1

a) heat lost by conduction = kAdT/dx

where K = thermal conductivity of pipe

A = cross sectional area

dT/dx = thermal gradient

= 0.045*pi*0.05^2 * (90 -40) / 0.2

= 0.088 W

b) heat lost =0.045*pi*0.05^2 * (90 -40) / 0.1

= 0.17 W

Answer 2

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