Shock or Rarefaction?(reflection of shock wave on contact interface)
 

I have a question about reflection of a shock from a contact surface. what occurs when it reach to the contact surface of two fluids with different properties?
the main question is:
when it reflects as another shock and when as a rarefaction wave as well as transmitted shock? whats the condition of it(shock or expansion)?
(although I've read some articles about Richtmeyer-Meshkov instability that this problem should be described there but didn't find a source that clearly explain it) :confused:

I don't really know what a Richtmeyer-Meshkov instability is but it seems to me that you're describing the shock-tube problem for which you can find a good description in Anderson's Modern Compressible Flow with historical perspective.

Hi dear Lefteris
you understood rightly about shock tube. I've found the answer to my question in an old references! it was so interesting.now,I haven't more time to describe but if anyone wanted to know more please just say to me.