Investigation of the wing design and endurance of an ultralight electrical aircraft

Abstract: The goal of this thesis was to explore the conversion of a propeller driven two-seater combustion airplane to an electrical airplane. Four different wing designs were considered. Two variations of Blackwing Sweden AB’s current Blackwing wing (BW), a longer wing (BW-L) and a shorter wing (BW-S), as well as a new wing with a different airfoil (GW). Using Computational Fluid Dynamics the wings were modelled for different angles of attack to explore the aerodynamic properties. The range and endurance of the wings as well as the minimum and maximum velocities were analysed. The computational modelling was conducted with both the SST k-ω and the Transitional SST turbulence model. The transitional model takes the laminar boundary layer into account, providing a more accurate result, since the wing profiles are laminar. GW was found more sensitive to the turbulence model used, and it was deducted that it was less robust than the BW wings. By varying the specific energy of the batteries in the airplane, the required energy needed to achieve the two hour flight target set by the company was explored. The airplane was compared to similar electric airplanes to analyse the market competitiveness. The results concluded that GW had the best range and endurance, however the cost would be higher, since it would require new tools to be produced. The recommendation to the company is to continue with the wing that had the second best range and endurance, BW-L.