Axisymetric cone flare

omar

I am using a 3D Finite Volume solver to compute the flow around a cone flare. The flow is hypersonic so I use a shock capturing method because of my very fine mesh. The problem is that, instead of doing a 3D computation, I have a 2D mesh (because the problem is axisymetric) to reduce the cost of the computation. Indeed, I have to impose a boundary condition at the symetry line and two periodic boundary conditions at each face. It seems that my boundary condition formulation (imposing at the ghost cells below the symetry line the same velocity as in the flow in the x-direction, a velocity in the y-direction and z-direction in an opposite direction, and the same pressure) doesn't work at all. I have very bad results and the "leading edge" is not at the symetry line. Do you have any idea whether it is coming from the nature of the problem (hypersonic flow with strong shock)? How to impose the bc's at the symetry line. Thank you very much for your attention, Omar S.