Study of the drone propulsion system for high altitude operations

The following thesis, carried out in collaboration with the company Pro S3 s.r.l., consists in the study of the propulsion system of a quadricopter drone, with the aim of developing four propellers for vertical take-off and a propeller for horizontal flight. The Skywalker X8 drone must operate at an altitude of 4000 m. The theories used are: Simple Impulsive Theory, Extended Impulsive Theory, Vortex Theory, Blade Element Theory, and Linearized theory of the actuator disk. Firstly, the drone characteristics and the operating environment, characterized by a density of 0.86 kg/m^3, are exposed; the density is of central importance because, by calculating the Reynolds number, it contributes to the determination of the flow. Later, the Simple Impulsive Theory and the Extended Impulsive Theory are discussed and applied by considering a determined number of scenarios characterized by masses and variable diameters. The aim concerns the determination of the induced power and the induced speed for each scenario. The application of the Vortex Theory allows to calculate the vorticity distribution under optimal conditions by determining the load parameter of Glauert (G) using an iterative method. Moreover, this theory is applied both to a disk with an infinite number of blades and to a disk with finite number of blades, considering, at the same time, the losses at the tip by using the Prandtl factor. The Linearized theory of the actuator disk identifies the motion field induced by the propeller. Finally, the results obtained from the application of these theories, the profiles used, with the corresponding performance calculated with XFOIL, and the motion field results are reported.