A CFD Study of the Effect of a Surface Roughness on Heat Transfer in a Clearance and Cooling Fins of an Electric Motor
Loading...
URL
Journal Title
Journal ISSN
Volume Title
Helsinki University of Technology |
J Muu elektroninen julkaisu
Unless otherwise stated, all rights belong to the author. You may download, display and print this publication for Your own personal use. Commercial use is prohibited.
Authors
Date
2004
Major/Subject
Mcode
Degree programme
Language
en
Pages
29
Series
Abstract
Abstract: The effect of a surface roughness on heat transfer is studied in two electric-motor-related cases. A flow in a clearance and between the cooling fins of the ABB HXR 400L electric motor is simulated numerically. The clearance is simplified to a two dimensional slot and, therefore, the calculation is not valid in the ends of the rotor. Furthermore, the clearance is modelled utilizing symmetry and only a sector of 30◦ is modelled. The air flow around the cooling fins is modelled by calculating one fin space and its surroundings. FINFLO flow solver, developed at Helsinki University of Technology, is used in the simulations. For the turbulence modelling k-ω model is utilized. Main result: A surface sand-roughness of 46 µm is used in a case of the clearance of an electric motor. The improvement of the equivalent conductivity is 0.4 % with open key slots and 4 % with filled key slots. A surface roughness of 1.5 µm has no effect on the heat transfer coefficient in a flow around the cooling fins while a roughness of 260 µm improves heat transfer coefficient by 1.8 %.Description
MEMO No CFD/THERMO-47-2004
Date: 4th March 2004
Keywords
FINFLO, k-ω-model, electric motor, clearance, cooling fin, surface roughness