Problem $3$ CLO $3$

A pipe has an outer surface of diameter $D_0=100mm$ and a tenperature $I_s=200C.$ The

outer surface of the tube is exposed to air for which $T_{}=30C$ and $h_{}=30\frac{W}{m^2}.K.$

a$)$ Draw a schematic diagram of the problem and calculate the heat loss from the pipe

per unit length.

An insulation layer $(k=0\mathrm{.}5\frac{W}{m}.K)$ of thickness $50$ mm is added on the outer surface of the

pipe to decrease the heat loss.

b$)$ Draw the complete equivalent thermal circuit.

c$)$ Calculate the heat loss from the pipe per unit length after adding the insulation

layer. The pipe outer surface $T_s$ is maintained at $200C.$

d$)$ Find the temperature of the outer surface of the insulation layer.