Fluid flow and heat transfer analysis of TEFC machine end regions using more realistic end-winding geometry

Abstract

Here, a typical small low-voltage totally enclosed fan-cooled (TEFC) motor (output power ∼10 kW) has been studied using computational fluid dynamics. The complexity of the end-winding geometries, often consisting of several insulated copper strands bound together, provides a challenge to the modelling and analysis of heat transfer and fluid flow phenomena occurring in the end region, which typically is an area of most interest for thermal management. Approximated geometries are usually employed in order to model the end windings to reduce the analysis time and cost. This paper presents a comparison of two cases, a typical simplified geometry and a more realistic geometry of end windings, and uses these cases to highlight the challenges and impact on predicted heat transfer. A comparison of the two models indicate that the different representations of end winding geometries can affect the heat dissipation rate through the outer housing by up to 45%.

Keywords

• machine windings
• heat transfer
• fans
• computational fluid dynamics
• thermal management (packaging)
• thermal management
• end-winding geometry
• heat dissipation rate
• end winding geometries
• typical simplified geometry
• analysis time
• fluid flow phenomena
• insulated copper strands
• end-winding geometries
• computational fluid dynamics
• low-voltage totally enclosed fan-cooled motor
• TEFC machine end regions
• heat transfer analysis