Influence of forebody cross-sectional shape on delta wing vortex burst location

3D steady Reynolds-averaged Navier-Stokes equations together with a shear stress transport (SST) turbulence model are applied for the numerical simulation of vortex burst over a chine forebody/delta wing configuration and a tangent-ogive forebody/delta wing configuration respectively in the subsonic case. The results show that compared with the tangent-ogive forebody, at moderate and high angles of attack, the chine forebody vortex contains a higher concentration of vorticity which is also very strong. As it enters the wing flow field, it can couple closely with the wing vortex, thus completely changing the wing vortex strength distribution and remarkably delaying the wing vortex burst. On the basis of the above, the mechanism is investigated by which the chine forebody can delay delta wing vortex burst. Through analyzing and comparing the simulation results, it can be concluded that: (1) The forebody cross-sectional shape has a significant influence on the distribution of the wing vortex strength; (2) The distribution of the wing vortex strength has a significant effect on the wing vortex burst location. Trying to keep the vortex strength gradually on the rise so as to create a favorable pressure gradient along the axis of the vortex is therefore an important way to delay the wing vortex burst.