ESR10 | Emilio Lopez Figueiras

With commercial aviation growing in importance every year and the need to reduce the fuel consumption and the emissions of greenhouse effect gases, it is required to reduce the aircraft aerodynamic drag as much as possible. Nowadays, the velocity of big commercial airplanes lays on the transonic regime and the use swept wings is well established. In such wings a phenomenon called “cross-flow” appears and triggers the transition of the flow from laminar to turbulent, generating a notable increase in the wing aerodynamic drag.

Among the strategies applied to avoid the fast transition to turbulent flow produced by cross-flow, the ones related with the wing surface roughness close to its leading edge seem to be more effective for free-flight conditions; including the natural roughness of the wing surface or artificial roughness elements added during the design process. This subject, despite been researched for decades, still sets many unknowns about how roughness interacts with different flow conditions or how its size or shape can affect the transition process to reduce drag in real flight conditions.

This project aims to solve some of these unknowns with the application of fluid numerical simulations, CFD techniques and flow stability analysis that, in combination with experimental results, can predict the behaviour of the flow for different roughness configurations or flight conditions in order to delay the transition to turbulence, reduce the drag in future aircraft and make them more sustainable and efficient.
Photos related with research for outreach.