Akademik Veri Yönetim Sistemi
AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022, California, Amerika Birleşik Devletleri, 3 - 07 Ocak 2022, (Tam Metin Bildiri)
Coning simulates motions encountered during spin and it can be visualized as a cone formed by the aircraft. An aircraft in fully developed spin displays a coning motion, which can be described as aircraft’s longitudinal axis rotating about wind direction axis (velocity vector) such that aircraft’s center of gravity lies on the wind direction axis. Two extremes of coning are yawing motion perpendicular to wind axis and rolling motion parallel to wind axis. Coning motion is a complex aerodynamic phenomenon and very difficult to capture using CFD. An attempt has been made to understand this coning motion for a supersonic aircraft using commercially available CFD software. The results from CFD analysis are compared with available wind tunnel data, because of complex nature of this type of testing the number of facilities having rotary rigs in their wind tunnels is small which further increase the importance of using CFD for such simulations. The CFD is performed on a full-scale aircraft whereas wind tunnel results are of a 1:13 scale model. For wind tunnel testing aircraft model is supported with a rear sting for angles of attack less than 45° and with a dorsal sting for angles of attack more than 45°. Wind tunnel testing was performed for a specific range of rotation rate which is scaled for CFD calculations. In addition to this range CFD calculations were performed for an enhanced range in order to be representative of a realistic aircraft scenario. The simulations were carried out using Shear Stress Transport (SST) k-ω turbulence model at four different angles of attack i.e., 15°,40°,50°,60°. Aerodynamic forces and moments coefficients obtained as a result of CFD simulations show an agreement with wind tunnel data for angles of attack 15° and 40°. While angles of attack 50° and 60° show a difference in lateral forces and moments due to the presence of dorsal sting attachment for angles of attack higher than 45°, lack of model/attachment bias wind tunnel testing and geometric imperfections in wind tunnel model. This analysis can contribute to better understand aircraft spin and spin recovery characteristics utilizing aerodynamic data as inputs for a 6 DOF mathematical model.