Andrey V. Novikov
DOI Number XXX-YYY-ZZZ
Conference Number HiSST 2018-1037
Direct numerical simulations of three-dimensional wave trains propagating in a boundary layer over 7 ◦ half-angle sharp cone at the freestream Mach number 5.95 are carried out. The Navier–Stokes equations are integrated using the in-house HSFlow solver implementing an implicit finite-volume shock-capturing method. Unsteady disturbances are imposed via a local suction-blowing actuator working at a fixed comparatively low frequency. The forced disturbances are transformed into a three-dimensional wave train dominated by oblique waves of the first mode. The disturbances grow downstream and ultimately exhibit weak nonlinear harmonics interactions in case of the moderate forcing level or demonstrate nonlinear breakdown into a “young” turbulent wedge in case of stronger forcing. Comparison is made with the controlled experiments at ITAM SB RAS, Novosibirsk performed on a cone with a disturbances actuator of glow discharge type. The computed azimuthal wavenumber spectra in case of moderate forcing are in good agreement with the experimental data. This and similar numerical simulations help to setup and interpret controlled experiments in wind tunnels as well as investigate laminar-turbulent transition mechanisms in boundary layer at high speeds.