Through a combination of large eddy simulations (LES), operator-based and data-based analysis methods, this work will study compressible turbulent flows over airfoils. This topic is extremely relevant to the design of modern aircraft as their aerodynamic performance, while operating in turbulent flow conditions, can be significantly impacted by compressibility effects. As the Mach number increases, shocks and expansion waves emerge interacting with boundary layers developing over a surface. This problem becomes increasingly challenging for wings undergoing flow separation. Whether at static or dynamic stall conditions, the presence of shocks and expansion waves can substantially modify the boundary layer characteristics, altering the separation and reattachment locations, harnessing flight stability, and posing a challenge to flow control. Such critical problems are encountered in a wide range of aviation applications, such as helicopter blades, rotorcraft, turbine cascades, and many others. Over the years, several experimental studies, mathematical models, and computational fluid dynamics methods have been employed to predict, study, and control turbulent compressible flows. Although these approaches have significantly expanded our knowledge of the physics of compressible turbulence, the complexity of the nonlinear flow evolution at the Reynolds and Mach numbers appropriate to the aircraft operation is still not completely understood, especially in high-speed flow regimes. To address this issue, this project proposes to employ LES with high-resolution schemes to study flow conditions consistent with those encountered in rotorcraft. Our proposal aims to study flows with complex and intrinsic transient nature. Such transient and often non-harmonic problems call for proper statistical and mathematical techniques to analyze the coherent turbulent structures present in the flow field in a time-varying manner. The methods developed to interpret and study the physics of compressible stall can further support the understanding of supersonic flows over blades with static laminar separation bubbles and other complex shock-turbulence applications with the aim to reveal the physical mechanisms that dominate turbulent compressible flows.
News published in Agência FAPESP Newsletter about the scholarship: