Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN CD: 1-56700-226-9

ISBN Online: 1-56700-225-0

International Heat Transfer Conference 13
August, 13-18, 2006, Sydney, Australia

Laminar Mixed Convection in the Entrance Region of Semicircular Duct

Get access (open in a dialog) DOI: 10.1615/IHTC13.p15.20
13 pages

Abstrakt

Laminar mixed convection in the entrance region for horizontal semicircular ducts with the flat wall in the vertical position has been investigated. The governing momentum and energy equations were solved numerically using a marching technique with finite control volume approach following the SIMPLER algorithm. Results were obtained for thermal boundary condition of uniform heat input axially and uniform wall temperature circumferentially (H1 thermal boundary condition) with Pr=0.7 and a wide range of Grashof numbers. These results include velocity, temperature distributions and secondary flow patterns, at different axial locations, covering all aspects of flow, axial distributions of local Nusselt and local wall friction factor. It was found that the Nusselt numbers were close to the forced convection values near the entrance region and then decreases to a minimum as the distance from the entrance increases and then rises due to the effect of free convection before reaching a constant value (fully developed value). As the Grashof number increases Nusselt number and wall friction factors increases in both developing and fully developed regions.