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

This is an open access article published by the IET under the Creative Commons Attribution-NoDerivs License (http://creativecommons.org/licenses/by-nd/3.0/)
Received 21/06/2018, Accepted 27/07/2018, Published 22/01/2019

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%.

Inspec keywords: computational fluid dynamics; machine windings; fans; thermal management (packaging); heat transfer

Other keywords: TEFC machine end regions; computational fluid dynamics; typical simplified geometry; analysis time; end-winding geometries; low-voltage totally enclosed fan-cooled motor; fluid flow phenomena; heat dissipation rate; heat transfer analysis; end-winding geometry; insulated copper strands; thermal management; end winding geometries

Subjects: Heat and thermodynamic processes (mechanical engineering); Applied fluid mechanics; Convection and heat transfer; Product packaging; Fluid mechanics and aerodynamics (mechanical engineering); General fluid dynamics theory, simulation and other computational methods

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