Estimation and reduction of drag in fuselage of solar powered UAV

This research aims to optimize the fuselage geometry of Solar Unmanned Aerial Vehicle, in order to obtain minimal drag. Fuselage is found to be one of the major contributors to drag. Thus, a methodology is established consisting of 5 prominent phases. First, a Preliminary Fuselage, capable of hosting the various components that need to be secured within the fuselage of a Solar UAV is developed. Second, the drag coefficient on this fuselage is estimated using a flow analysis software, ANSYS® Fluent®. Thirdly, the geometry of the fuselage is then iterated using a code written on MATLAB® R2015a and XFOIL without compromising on the component layout, until an optimized geometry offering minimal drag is arrived. The next phase involves the development of fuselage using modelling software. The final phase involves drag coefficient estimation for the optimized fuselage. The results of the optimized fuselage are then compared with that of the preliminary fuselage. Also, the drag coefficient estimation on the generated splines are validated by verifying the results of ANSYS® with the results of XFOIL. It is seen that the drag coefficient and hence the drag force on the optimized fuselage is significantly less than the preliminary fuselage. The immediate consequence of drag reduction is a reduction in thrust required for steady flight, thereby reducing the power consumption. Reduced power consumption implies increased endurance for Unmanned Aerial Vehicles. Increasing endurance will lead to enhanced capabilities and applications. This methodology may be adopted to a variety of fuselages of conventional Unmanned Aerial Vehicles which are currently designed empirically.