NUSSELT NUMBERS IN LAMINAR-FLOW FOR H2 BOUNDARY-CONDITIONS

The present analysis deals with the velocity and temperature distribut ion in steady state, hydrodynamically and thermally fully developed, l aminar forced flow for Newtonian fluids in rectangular ducts. The anal ytical solutions are presented for all the eight modified H2 thermal b oundary conditions around the periphery of the duct cross-section. The velocity profile represents the rigorous solution to the Navier-Stoke s equation; the temperature profile is obtained resorting to series so lutions of trigonometric functions. The temperatures and the Nusselt n umbers are predicted as functions of the aspect ratio and compared wit h the results available in literature. Finally, very simple polynomial representations are given for the Nusselt numbers.