The conduction of heat through series combinations of rods is shown below.
The expression of the rate of heat flow for series conduction is,
=== = = Substitute
A1=A2=A3 and
l1= l2=l3 in above expression,
2k(100−T1)=k(T1−T2) =0.5( T2−0) ...... (I)
The equivalent coefficient of thermal conductivity,
=++ keq= The heat current equation is,
= = ...... (II)
The equivalent length is,
l=l1+l2+l3=3l1 The equivalent area is,
A=A1+A2+A3=3A1 Substitute values in equation (II)
= ×100=100−T1 T1= Substitute values in equation (I),
2k (100−)=0.5kT2 T2=