Innovative aircraft studies often involve disruptive engine integration concepts, such as distributed propulsion, boundary-layer ingestion or unducted fan strongly interacting with the airframe. For such designs, airframe-engine aerodynamic interaction must be taken into account starting from the early design phase, with the need for computational-...
The exergy concept originates from the field of static thermodynamics and expresses the maximum theoretically recoverable mechanical work from a system while it evolves towards its dead state (corresponding to the state in which the system is at a thermodynamic equilibrium with its environment). It accounts for both mechanical and thermal mechanism...
The growing interest in civil supersonic flight is driving research in this direction, with a focus on reducing environmental impacts such as fuel consumption and noise [1]. These are the two fundamental objectives that have motivated the research work at ONERA, reported in this paper. To reduce these two phenomena, it is essential to pay attention...
The first objective of the thesis is to characterise the role of the local aerodynamic unsteadiness introduced by thick aerofoils equipped with root aerodynamic add-on. A special focus will be on the aerofoil loads, turbine lifetime and turbine energy production. The thesis aims at understanding the aerodynamic causes of the structural failure usin...
optimized aerodinamic insert for a vehicle wheel
Insert à l'aérodynamique optimisée pour une roue de véhicule
Le cycle de Miller est utilisé pour améliorer le rendement par détente prolongée. Celle-ci étant réalisée en diminuant le taux de compression effectif par fermeture prématurée des soupapes d’admission. Le mouvement aérodynamique, interne aux cylindres, cesse donc d’être entretenu avant que le piston n’atteigne le point mort bas. Or, ce mouvement es...
Increasing the wing aspect ratio appears as a straightforward way to improve aerodynamic performance of transport aircraft by reducing the lift-induced drag component. However, it comes at the price of a direct negative impact on the wing structural weight which is necessary to sustain aerodynamic loads in the case of a conventional cantilever wing...
The expected performance of engineering systems can significantly differ from their operational performance due to the variability of some parameters they depend on. Usually, the design stage of these systems is divided into two different phases. The first phase consists in determining the pre-optimal design. Through the use of numerical simulation...
Accurately predicting the lift and the drag exerted on aircraft has always remained essential for the designer. In order to develop the future commercial aircraft that minimize fuel burn and hence operating costs and environmental footprint, the designer needs to clearly identify the phenomenological sources of lift and drag. This is done by means ...
