Viscous heating in laminar tube flow 

(a) Continue the analysis begun in Problem 11B.2--namely, that of finding the temperature profiles in a NewtonJan fluid flowing in a circular tube at a speed sufficiently high that viscous heating effects are important. Assume that the velocity profile at the inlet (z = 0) is fully developed, and that the inlet temperature is uniform over the cross section. Assume all physical properties to be constant. 

(b) Repeat the analysis for a power law non-Newtonian viscosity.