Determination of fan design parameters for light-sport aircraft


  • Jan Klesa Czech Technical University, Faculty of Mechanical Engineering, Department of Aerospace Engineering, Karlovo náměstí 13, Prague 2, Czech Republic



ducted fan, electric propulsion, axial compressor


This paper is focused on the preliminary design of an electric fan for light-sport aircraft. Usage of electric motors brings some advantages compared to piston engines, especially small size and the independence of power on shaft RPM. A 1D compressible fluid flow model is used for the determination of the performace. The influence of various system parameters is analysed. Results for the case of the UL-39 ultralight aircraft are presented. Finally, input parameters for the fan design are determined according to this analysis. This can be then used as input data for the standard fan (axial compressor) design procedure.


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