**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**30184

##### Air flow and Heat Transfer Modeling of an Axial Flux Permanent Magnet Generator

**Authors:**
Airoldi G.,
Bumby J. R.,
Dominy C.,
G.L. Ingram,
Lim C. H.,
Mahkamov K.,
N. L. Brown,
A. Mebarki,
M. Shanel

**Abstract:**

Axial Flux Permanent Magnet (AFPM) Machines require effective cooling due to their high power density. The detrimental effects of overheating such as degradation of the insulation materials, magnets demagnetization, and increase of Joule losses are well known. This paper describes the CFD simulations performed on a test rig model of an air cooled Axial Flux Permanent Magnet (AFPM) generator built at Durham University to identify the temperatures and heat transfer coefficient on the stator. The Reynolds Averaged Navier-Stokes and the Energy equations are solved and the flow pattern and heat transfer developing inside the machine are described. The Nusselt number on the stator surfaces has been found. The dependency of the heat transfer on the flow field is described temperature field obtained. Tests on an experimental are undergoing in order to validate the CFD results.

**Keywords:**
Axial flux permanent magnet machines,
thermal modeling,
CFD.

**Digital Object Identifier (DOI):**
doi.org/10.5281/zenodo.1076832

**References:**

[1] G. Airoldi, G.L. Ingram, K. Mahkamov, J.R. Bumby, R.G. Dominy, N.L. Brown, A. Mebarki and M. Shanel "Computations on Heat Transfer in Axial Flux Permanent Magnet Machines" IEEE Proceedings of the 2008 International Conference on Electrical Machines.

[2] J. Pelle- and S. Harmand "Heat transfer measurements in an opened rotor-stator system air-gap", Experimental Thermal and Fluid Science, (2007), pp 165-180.

[3] Z. X. Yuan, N. Saniei and X. T. Yan, "Turbulent heat transfer on the stationary disk in a rotor-stator system", International Journal of Heat and Mass Transfer, (2003), pp 2207-2218.

[4] S. Harmand, B. Watel, B. Desmet, "Local convective heat exchanges from a rotor facing a stator" Int. J. Therm. Sci, (2000), pp 404-413.

[5] R. Boutarfa, S. Harmand, "Local convective heat exchanges and flow structure in a rotor-stator system", Int. J. Therm. Sci. (2003), pp 1129- 1143.

[6] J. Pelle- and S. Harmand, "Heat transfer study in a rotor-stator system air-gap with an axial inflow", Applied hermal Engineering, (2009), pp 1532-1543.

[7] Fluent.Inc. "Computational Fluid Dynamic Software", User's guide release 6.3, Lebanon, NH, USA, 2006

[8] J. W. Daily, R. E. Nece, "Chamber dimension effects on induced flow and frictional resistance of enclosed rotating disks", Transactions of the ASME. Series D, Journal of Basic Engineering, (1960), pp 217-232.

[9] S. Poncet, M. P. Chauve and R. Schiestel, "Batchelor versus Stewartson flow structures in a rotor-stator cavity with throughflow", Physics of fluids, (2005).

[10] G. K. Batchelor, "Note on a class of solutions of the Navier-Stokes equations representing steady rotationally-symmetric flow", Q. J. Mechanics Appl. Math, Vol. 4, (1951), pp 29-41.

[11] Stewartson, K., "On the flow between two rotating coaxial disks", Mathematical Proceedings of the Cambridge Philosophical Society, (1953) pp 333-341.