Heat Transfer in the Entrance Region of Tubes that Rotate about a Parallel Axis

Abstract

The paper presents the results of an investigation into the effect of rotation on heat transfer in the entrance region of circular tubes that are constrained to rotate about an axis parallel to the symmetry axis. This rotating geometry is an important feature of flow systems designed for cooling the rotor windings and armature drums of electrical machines and other prime movers. It is demonstrated that rotation tends to improve local and mean heat transfers, and correlating equations are proposed for turbulent and laminar flows.