Experimental results are presented for forced convection in the entrance region of a pipe; the results were obtained using both the boundary condition of uniform heat flux and that of uniform temperature. A significant difference which is attributable to the different boundary conditions was observed for Reynolds numbers below about 3 times 104, but at higher Reynolds numbers the difference rapidly diminishes.
An approximate numerical solution for the early stages of boundary layer formation on the pipe walls gave similar differences between the two boundary conditions as were observed in the experiment.
Get full access to this article
View all access options for this article.
References
1.
MillsA. F.‘Experimental investigation of turbulent heat transfer in the entrance region of a circular conduit’, J. mech. Engng Sci.19624 (No. 1), 63.
2.
EckertE. R. G.DrakeR. M.jun.Heat and mass transfer1959 (McGraw-Hill Book Co., Inc., London and New York).
3.
SleicherC. A.TribusM.‘Heat transfer in a pipe with turbulent flow and arbitrary wall temperature distribution’, Trans. Amer. Soc. mech. Engrs195779, 789.
4.
HallW. B.PriceP. H.‘The effect of a longitudinally varying wall heat flux on the heat transfer coefficient for turbulent flow in a pipe’, Proc. 1961-62 Int. Heat Transfer Conf. (paper 72), 607 (American Society of Mechanical Engineers, New York).
5.
HowarthL.‘On the solution of laminar boundary layer equation’, Proc. roy. Soc.1938164 (Series A), 547.
