Regular technical meeting of the BUTERFLI project held at TsAGI

On October 6-7, 2014 the third technical meeting of the BUTERFLI (BUffet and Transition delay control investigation within European-Russian cooperation for improved FLIght performance) project was held at the Central AeroHydrodynamic Institute named after Professor N.E. Zhukovsky. The objective of the project is the research of buffeting and laminar-turbulent boundary layer transition control to improve aircraft aerodynamic characteristics. The project was started in 2013 under the auspices of the 7th Framework Programme of the EU and brought together the leading Russian and European research organizations. The Russian project coordinator is FSUE TsAGI; the project coordinator from the EU is the French aerospace research center ONERA.

Wing flow control, improvement of its bearing and aerodynamic characteristics and, as a consequence, improvement of aircraft fuel efficiency are the main tasks of the scientists who joined forces working on the BUTERFLI project. To complete these tasks, researchers are developing two key concepts: delay of the start of buffeting on supercritical wings and delay of the laminar-turbulent boundary layer period on profiles and wings.

“The project aims to address buffeting issues — undesirable aerodynamic phenomenon involving vibrations of the aircraft during stalling on airfoils (wing or tail) at high angles of attack,” said Sergei Lyapunov, deputy director general of TsAGI, head of the Aerodynamics and Aircraft Flight Dynamics Department. “Buffeting limits the ability of the aircraft to achieve required speed and altitude. The project examines approaches to combat this phenomenon, based on influencing the flow using plasma, air jets blows, etc.”

In addition to TsAGI, Russian participants of the BUTERFLI project include the Moscow Institute of Physics and Technology (MIPT), the Joint Institute for High Temperatures, the Russian Academy of Sciences (RAS JIHT), CJSC “Sukhoi Civil Aircraft” (JSC “SCA”), and the Khristianovich Institute of Theoretical and Applied Mechanics (ITAM SB RAS). Europe, in addition to ONERA, is represented by DLR, Airbus group, the University of Stuttgart, the Royal Institute of Technology in Sweden, the University of Nottingham, and ERDYN.

The participation of TsAGI in the project involves both computational research and experiments in wind tunnels. To date preliminary numerical simulation has been completed to determine the necessary parameters for future research. Experimental tests through the Institute are scheduled for the next year.

Commenting on the results of the meeting, Sergei Lyapunov noted: “Working together is a success — this is the general opinion shared both by Russian and European participants. We are on the way to important results that, after experimental studies, will be of great value to aviation science.”