  The present study addresses the self-similar problem of unsteady shock
reflection on an inclined wedge. The start-up conditions are studied by
modifying the wedge corner and allowing for a finite radius of curvature. It is
found that the type of shock reflection observed far from the corner, namely
regular or Mach reflection, depends intimately on the start-up condition, as
the flow "remembers" how it was started. Substantial differences were found.
For example, the type of shock reflection for an incident shock Mach number
$M=6.6$ and an isentropic exponent $\gamma =1.2$ changes from regular to Mach
reflection between $44^\circ$ and $45^\circ$ when a straight wedge tip is used,
while the transition for an initially curved wedge occurs between $57^\circ$
and $58^\circ$.
