Development and application of a new unsteady far-field drag decomposition method

H. Toubin (1) , D. Bailly (1)

1 ONERA - The French Aerospace Lab [Meudon]

Far-fi eld decomposition methods are among the most powerful means to accurately compute the forces on an aircraft. They allow distinguishing between the drag components associated with the various physical phenomena: shock waves, viscous interactions and lift-induced vortex, without yet being fit to apply to unsteady confi gurations. Van der Vooren and Destarac have for example developed a powerful and reliable method used widely in the industry but restricted to steady flows. Gari epy has made a first attempt in generalizing it but his decomposition still holds terms that cannot be matched with physical phenomena. This paper presents another generalization to unsteady flows of Van der Vooren formulation. The demonstration relies on a strong theoretical background and allows the breakdown of drag into the three usual components only. This new unsteady formulation is applied to an OAT15A profi le with bu ffeting, then to a NACA0012 pro file at high angle of attack with natural vortex shedding, and finally to an oscillating profi le. The results are analyzed and compared to the only other formulation available to break down the drag of unsteady confi gurations.

Keywords: DRAG; UNSTEADY; DECOMPOSITION

Domains: Engineering Sciences [physics]; Reactive fluid environment

H. Toubin, D. Bailly. Development and application of a new unsteady far-field drag decomposition method. AIAA AVIATION 2014, Jun 2014, ATLANTA, United States. ⟨hal-01069591⟩