Extending the aircraft flight envelope by mitigating transonic airfoil buffet
by Esther Lagemann, Steven L. Brunton, Wolfgang Schröder, Christian Lagemann

arXiv: https://arxiv.org/abs/2401.08894

In the age of globalization, commercial aviation plays a central role in maintaining our international connectivity by providing fast air transport services for passengers and freight. However, the upper limit of the aircraft flight envelope, essentially the maximum aircraft speed, is usually fixed by the occurrence of a safety-critical aerodynamic phenomenon called transonic airfoil buffet. It refers to shock wave oscillations occurring on the aircraft wings, which induce unsteady aerodynamic loads acting on the wing structure. Since these loads can cause severe structural damage endangering flight safety, the aviation industry is highly interested in suppressing transonic airfoil buffet to extend the flight envelope to higher aircraft speeds. In this contribution, we demonstrate with experimental wind tunnel measurements that the application of porous trailing edges substantially attenuates the buffet phenomenon. Since porous trailing edges have the additional benefit of reducing acoustic aircraft emissions, our findings could pave the way for faster air transport with reduced noise emissions.