WENO scheme ghost points
 

Hi guys,
I am writing finite difference WENO solver with LF flux splitting scheme. I have some doubts in that.

1) I am using stencil (i-2 to i+2) for calculation of flux at i+1/2(+) and i-1/2(-). And stencil (i-1 to i+3) for getting flux at i+1/2(-) and i-1/2(+). Is this correct?

2) In the flux splitting the eigen vectors for the flux jacobian are obtained at A(U)at i+1/2.. Here, in the eigen vectors, the metric derivatives are needed at i+1/2 and i-1/2. How to obtain metric derivatives at these points as i have metric derivatives at (i-1,i and i+1).

3) in 2d case i need three ghost points. based on boundary i use either reflective boundary or non reflective boundary condition for ghost points. How to handle metric derivatives for ghost points?? I am getting disturbances from the boundary points...

Kindly help me

Regards
vasu