A CFD benchmark of active flow control for buffet prevention

Abstract

This paper will present the main results of the aerodynamic design and analysis for flow control applied to trailing edge of wings and profiles. This work has been conducted in the framework of the European project AFLoNext aiming at developing technologies allowing for an improvement of the performance and loads situation in the operational domain. The technologies are expected to provide an increase in aerodynamic efficiency and a structural weight reduction for the design flight conditions with a potential for 1-2% fuel savings and corresponding emission reduction. Numerical simulations are performed on 2D and 3D test cases. Where available, a comparison with experimental data is performed. High-speed flow is considered, in order to investigate a transonic configuration representative of cruise conditions. Trailing edge devices (TED) such as fluidic Gurney flaps or micro-jets for circulation control are used for assessing the possibility of delaying the buffet onset or increasing the maximum achievable lift, thus extending the flight envelope of an aircraft. The purpose of the present paper is to present the result of the work performed by the different partners involved in the project.

Global stability analysis of elastic aircraft in edge-of-the-envelope flow

“…Nevertheless, our identification of the fluid and structural wakemakers could also be useful for realising effective control strategies for the buffet phenomenon, and the interested reader is referred to e.g. D 'Aguanno, Schrijer & van Oudheusden (2019) and Sartor et al (2020). Second, in figures 5 and 7(b), for the group of modes near angular frequency ω = 1.8, the Arnoldi method does indeed identify three unstable structural modes, specifically modes 19, 20 and 21, also found by the earlier flutter analysis.…”

Editorial for the CEAS Aeronautical Journal special issue on Active Flow Control research within the AFLoNext project

“…In the high-speed regime, flow separation control for buffet onset suppression offers benefits on the overall aircraft level either in speed flexibility or in wing weight reduction. The contribution of Sartor et al [6] provides an insight into a benchmark activity for validation and calibration of numerical simulation tools for buffet onset suppression influenced by AFC. This contribution has been awarded the EREA Best Paper Award 2019 as it reflects a collaborative action involving most European research institutions in aerodynamics.…”