
Forced Convection Heat Transfer: External Flows 229
and normalized temperature, T*, are the same for Pr = 1. This should be expected
since differential equations for df/dη and T*, are exactly the same if Pr = 1. It is also
seen that the temperature boundary layer thickness is larger than velocity bound-
ary layer thickness if Pr < 1 and is smaller than velocity boundary layer thickness
if Pr > 1.
The numerical solutions of Equations 10.48 and 10.49 were used to obtain the fol-
lowing expressions for the thicknesses of the velocity and thermal boundary layers,
the local friction coefcient and the local Nusselt number for low-speed laminar ow ...