The quest to reduce CO2 emissions in transport is driving research into flow control methods aimed at reducing the aerodynamic drag. Especially in air transportation, the roughly linear dependency of fuel consumption on aerodynamic resistance explains the need for innovative approaches to control turbulence that achieve substantial drag reduction.
Within this context, we explore an active flow control technique based on Streamwise Traveling Waves (StTW) of spanwise forcing. Through Direct Numerical Simulation (DNS) of compressible flow, we investigate its effect on aircraft wings in transonic conditions. Studies carried out so far on drag reduction are often limited to low-Reynolds-number, parallel-flow configurations, in which drag is entirely due to friction. Over an aircraft wing, however, the flow experiences pressure gradients and shock waves, and aerodynamic drag includes additional contributions.
The aim of this project is to understand how flow control techniques affect the overall aerodynamic efficiency of the wing, extending the predictive capabilities of DNS to Reynolds numbers relevant for practical applications. Focusing on the StTW of spanwise forcing, we aim to determine optimal control parameters in a realistic configuration, carrying out the first DNS of an airfoil wing at Reynolds number 1 million.
Sapienza University of Rome, Italy.