2019/08/01 by T. D. Bennett, Ted D. Bennett
Engineering · #Fluid Dynamics and Turbulent Flows #Heat Transfer and Optimization #Heat transfer and supercritical fluids
paper · doi:10.1115/1.4044390
openalex publication_date 2019/08/01 · crossref created 2019/08/01 · crossref issued 2019/09/27 · crossref published 2019/09/27 · crossref published-online 2019/09/27 · crossref deposited 2019/09/27 · crossref published-print 2019/11/01 · openalex created_date 2025/10/10 · crossref indexed 2026/07/31 · openalex updated_date 2026/07/31
Abstract A generalized correlation for combined entry convection in ducts of arbitrary cross section has been developed. The correlation is constructed for the average Nusselt number using knowledge of fully developed transport constants. The general correlation reproduces the first principle solutions for the well-established round and parallel plate duct geometries to within ±5% for both constant temperature and constant heat flux wall conditions when Pr ≥ 0.7. A survey of the literature demonstrates that the new generalized correlation performs as well or better than existing correlations, which are expressed for specific geometries and wall conditions. The new correlation is generally in good agreement with the first principle solutions of less common duct geometries so long as the duct has a convective surface equal to the wetted perimeter. The new correlation is not recommended for ducts having small aspect ratios that pinch the flow when convection is prescribed by the H2 constant heat flux wall condition.