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Rotocycloid propulsion presents interesting performance as a possible long-term alternative to helicopters in a far future. It will lead to increase the energy efficiency of VTOL vehicles. This paper focuses on optimization of an airship with the possibility up to 2000 h/year of photovoltaic propelled flight at a cruise speed about 20 m/s. This paper demonstrates the feasibility of this airship concept and presents a full dimensioning according to the CDE (Constructal Design for Efficiency) developed at University of Modena and Reggio Emilia. The proposed solution has been deeply analyzed and the analysis of performances has been presented. The results allow thinking to a novel class of vehicles designed specifically to take the maximum advantage by this propulsion method.

Cyclogiros have the possibility to provide hovering and achieve forward speeds higher than present day helicopters. Yet, due to the inherent unsteady aerodynamics, most of the research approaches have been based on limited experimental testing of computational fluid dynamics. However, and for a parametric analysis, it is important to provide analytic tools that can help in the preliminary design stage. In this work the complexity of the forward flight modeling will be described using an innovative approach. The present proposed model will be benchmarked against experimental and CFD results, further it will be used to propose rotor geometries for 3 working conditions.

The use of a magnetic field applied to a gaseous conducting boundary layer flow as been proposed as a mean to control boundary layer losses. The solution of the Navier-Stokes equations together with the induction equation for the magnetic field was numerically obtained using a Finite Volume code. The effects of the magnetic field are introduced into the momentum equations by means of a Lorentz force source term. Further, several turbulence models were modified in order to include the magnetic field perturbation. The computation of the transitional flow on a flat plate was made for several values of the magnetic field, and a relaminarization of the flow was obtained for sufficient high values of the magnetic field. The code was also applied for the computation of the flow around an airfoil as an example application of an high speed high-altitude UAV.