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Most aircraft designers prefer electric engines with open helices rather than ducted fan units. Open propellers often present a higher propulsive efficiency if compared to electric turbofans. High altitudes and rarefied atmosphere evidence this difference. A mathematical model to improve the performances of a ducted fan unit has presented. It aims to align the performances of the two systems by acting on the air intake of the ducted fan. It defines a simplified method for increasing the efficiency of an electric turbofan. It aims to produce a basic and solid mathematical model, which can apply to the study of this propulsion system. CFD simulations have verified the results. Two CFD codes have used to validate the results. An analysis of mesh independence has performed to ensure a better quality of the results. The presented model aims to reach also a methodological result.

This paper presents a coupled numerical and experimental study of an unconventional wing profile such as cp-180-050-gn (Cambered plate C = 18% T = 5% R = 0.78). This wing profile deals with low speeds. It is not currently used on any aircraft model. Otherwise, it presents interesting performances that can be exploited for the design of low-speed STOL or VTOL aircraft by mean of the very high lift that it can generate and can fit with different uses such as VAWT, cyclorotors drones, which are designed explicitly for low-speed operations. After a preliminary CFD assessment of the wing a complete experimental characterisation also at high angles of attack has been performed. The excellent agreement between CFD and experiments has allowed producing a complete analysis of the behaviour of the wing profile both before and after stall conditions. This study has the objective of analysing the viability of such an unconventional wing in traditional or over-stalling conditions.

This paper presents a model of energetic consumption and photovoltaic production for a large airship which acts as feeder connecting the ground with a large cruiser. The analysis of energy needs and productivity allows defining both an ideal sizing and operative mission profiles. The specialised mission of this airship is to ascent and descent. It includes also the connection with the airport buildings on the ground and with the cruiser at high altitude. Photovoltaic production has evaluated in terms of hydrogen and electric propulsion. They have estimated both and a calculation methodology has proposed. The evaluation has supported by CFD evaluations on aerodynamic behaviour of the system at various altitudes.

This paper presents the theoretic and numerical background of a recent patent about an innovative Coanda Effect application. This innovative jet is designed to enhance the controllability of the system and to encompass static deflection of the fluid jet but especially the dynamic variation of the Coanda deflection with a very low inertia. This innovative nozzle is formerly named H.O.M.E.R., acronym of “High-speed Orienting Momentum with Enhanced Reversibility”. H.O.M.E.R. constitutes an application based on a dual propeller system. It explains how a vector controllable flux can be produced, with the ability to change angular position dynamically as a function of momentum (or velocity) of the two primitive streams. CFD based simulation in a configuration is provided and main calculations are produced to define the control model. Nozzle design guidelines are provided. The proposed system can be used both for aeronautical naval propulsion and industrial applications.

An exhaustive model of Coandã effect has not been defined, and fundamental questions are still open. One of them is the influence of convective heat exchange on Coandã adhesion. This paper presents an even preliminary numerical study of this problem. It analyses the behaviour of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface. It approaches the problem by a set of CFD simulations, analyses previous hypotheses, which are based on Prandtl number, and evidences the need for a model that account Reynolds number. The performed simulations are still not sufficient for an exhaustive comprehension of Coandã effect in the presence of heat exchange phenomena. It allows producing some consideration that may help future scientific work in toward a better comprehension of these phenomena.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method.