Numerical investigation of standing oblique detonation supported by two-dimensional blunted wedge

A numerical analysis is performed on the characteristics of a standing oblique detonation (SOD) in front of a two-dimensional blunted wedge. The incoming hypersonic flow consists of a uniformly-premixed stoichiometric oxyhydrogen mixture diluted by 70% Argon. The incident Mach number is set at 6.0 which is higher than its Chapman-Jouguet value 4.8. When the sphere radius is L (chemical induction length of plane Chapman-Jouguet detonation), reaction front is decoupled from the leading shock wave. When the sphere radius is 3L, on the other hand, the unsteady SOD runs away to the upstream, because the heat release behind the oblique shock pushes the bow shock away from the body surface and changes the oblique shock angle closer to normal. Eventually the shock angle exceeds the limiting angle for the existence of the stationary oblique shock wave. The present study confirms that there are critical values for the incident Mach number and the wedge tip radius for the establishment of SOD in a hypersonic premixed gas.