A new aircraft architecture based on the ACHEON Coanda effect nozzle: flight model and energy evaluation

Abstract

Aeronautic transport has an effective necessity of reducing fuel consumption and emissions to deliver efficiency and competitiveness driven by today commercial and legislative requirements. Actual aircraft configurations scenario allows envisaging the signs of a diffused technological maturity and they seem very near their limits. This scenario clearly shows the necessity of radical innovations with particular reference to propulsion systems and to aircraftarchitecture consequently.\ud Methods\ud This paper presents analyses and discusses a promising propulsive architecture based on an innovative nozzle, which allows realizing the selective adhesion of two impinging streams to two facing jets to two facing Coanda surfaces. This propulsion system is known with the acronym ACHEON (Aerial Coanda High Efficiency Orienting Nozzle). This paper investigates how the application of an all-electric ACHEONs propulsion system to a very traditional commuter aircraft can improve its relevant performances. This paper considers the constraints imposed by current state-of-the-art electric motors, drives, storage and conversion systems in terms of both power/energy density and performance and considers two different aircraft configurations: one using battery only and one adopting a more sophisticated hybrid cogeneration. The necessity of producing a very solid analysis has forced to limit the deflection of the jet in a very conservative range (±15°) with respect to the horizontal. This range can be surely produced also by not optimal configurations and allow minimizing the use of DBD. From the study of general flight dynamics equations of the aircraft in two-dimensional form it has been possible to determine with a high level of accuracy the advantages that ACHEON brings in terms of reduced stall speed and of reduced take-off and landing distances. Additionally, it includes an effective energy analysis focusing on the efficiency and environmental advantages of the electric ACHEON based propulsion by assuming the today industrial grade high capacity batteries with a power density of 207 Wh/kg.\ud Results\ud It has been clearly demonstrated that a short flight could be possible adopting battery energy storage, and longer duration could be possible by adopting a more sophisticated cogeneration system, which is based on cogeneration from a well-known turboprop, which is mostly used in helicopter propulsion. This electric generation system can be empowered by recovering the heat and using it to increase the temperature of the jet. It is possible to transfer this considerable amount of heat to the jet by convection and direct fluid mixing. In this way, it is possible to increase the energy of the jets of an amount that allows more than recover the pressure losses in the straitening section. In this case, it is then possible to demonstrate an adequate autonomy of flight and operative range of the aircraft. The proposed architecture, which is within the limits of the most conservative results obtained, demonstrates significant additional ...

A New Propelled Wing Aircraft Configuration

“…The method allows evaluating cumulative exergy consumption also introducing an effective differentiation between non-renewable and renewable resource inputs according to Gong and Wall [8]. Trancossi [9][10] has modified the model by introducing an effective distinction of the energy needs for moving the vehicle and moving the payload. He does not consider the vehicle as a necessity, but he seeks by this approach to identify how the vehicle can be improved minimize its energy consumption.…”

“…Total power is consequently y x tot +P =P P (10) The total power required is obtained by rotor power and overall efficiency factor η is…”

Numerical Study of Turbulent Air and Water Flows in a Nozzle Based on the Coanda Effect

“…One illustration of the domain subjected to Coanda effect flow can be seen in Figure 1. Thus, the Coanda effect became the target of many studies where several mechanisms which were based on this effect were developed, such as cooling [3][4][5], safety devices [6], aerospace applications [7][8][9][10] and few recent studies in marine devices [11,12]. The Coanda effect is also important for the design of Unmanned Aerial Vehicles (UAV).…”

“…Moreover, a parametric study about the effect of the outlet height of device over fluid dynamic behavior of jet flow was performed. Afterwards, Trancossi et al [9] presented a work concerned with the application of a turbine based on a nozzle named ACHEON (Aerial Coanda High Efficiency Orienting Nozzle). The studied configuration allowed to perform a selective adhesion of jet flows (in two streams) over two Coanda surfaces.…”