Analysis of Vortex Flow Phenomena on Generic Delta Wing Planforms at Transonic Speeds

Abstract

This paper presents combined experimental and numerical investigations on the aerodynamics of a generic triple-delta wing configuration at transonic speeds up to high angles of attack with and without sideslip. Vortex flow effects such as vortex development, vortex-vortex and vortex-shock interactions are discussed for a particular wing planform, and selected results of wind tunnel tests and CFD computations are compared to each other. Thereby, a better understanding of transonic vortex flow phenomena observed is provided. The experimental analyses are based on measurements of forces and moments as well as surface pressures by pressure sensitive paint. The numerical investigations originate from URANS computations. Overall, it turns out that at low to medium angles of attack the results of both data sources are in acceptable agreement. At higher angles of attack, however, considerable discrepancies are noticed, both in the case of longitudinal and lateral motion. In particular, the experimental and numerical results emphasize a different prediction of vortex breakdown effects. These are – at the transonic conditions considered – highly linked to vortex-vortex and vortex-shock interactions.