A long thin copper rod K 377 Wm K 10 mm in diameter is expos

A long thin copper rod (K= 377 W/m K) 10 mm in diameter is exposed to an environment at 22 oC. The base temperature of the rod is maintained at 150 oC. The heat transfer coefficient between the rod and the environment is 11 W/m2 K. Calculate the rate of heat loss from the rod.

Solution

Given,

Diameter of rod, d=10mm=1 cm=0.01 m

Perimeter, P=pi*d=3.14*0.01=3.14*10^-2 m

Area of cross section, A_C=7.854*10^-5 m²

T_inf=22?

T_b=150 ?

h_fluid=11 W/m².K

K=377 W/m.K

Now,

Heat transfer from the rod=sqrt(hPKA_C)*(T_b-T_inf)

                                                =sqrt(11*3.14*10^-2*377*7.854*10^-5)*(150-22)

                                                =12.94 J/sec