ISSN Online: 2377-424X
ISBN Print: 0-89116-559-2
International Heat Transfer Conference 8
SOLUTIONS TO THE COMBINED ENTRANCE REGION IN A CIRCULAR TUBE
Abstract
This paper presents solutions to the laminar combined hydrodynamic and thermal entry region problem for the case of a circular tube with constant wall temperature. The momentum and energy equations are decoupled. The momentum equation retains the fully viscous terms as well as the inertial terms and the energy equation retains the axial conduction term. The solution to the momentum equation results in a developing velocity profile that is
valid over a large Re number range. from Re
→0 to Re→ ∞. The energy equation is solved using a numerical scheme and the solution to the momentum equation. The numerical scheme used is a finite difference SOR iteration procedure. The results for Pe < 100 (Pr < 5 ) show that axial conduction has a significant effect on the heat transfer. Specifically the inclusion of axial conduction results in a much longer thermal development length.