MacCormack Method for Axisymmetric Nozzle
 

Good Night everyone,

I'm having some trouble with my graduation project,it is about nozzles.

The aim is to make a code using Finite Differences MacCormack's method for both quasi-1D and axisymmetric nozzle(first whitout shock,and after with shock).

The quasi-1D solution worked very well,but i can't make the axisymmetric case work fine,at some point of the simulation something weird happens at the inlet boundary,and the solution blows up.

I've noticed that there is a sudden pressure drop just in the first row of cells after the inlet,and this happens with density and temperature either,no matter what I change... The pressure is reduced to 10% of the inlet value in large times. I think the problem is this,but maybe there are other things.

The most weird part is: the Mach number seems to be correct,and the velocity profiles too!

Does anyone know how to avoid this pressure drop??? The code can be downloaded in the link below! Also, there are some results of the simulation using p=10^7 Pa and T=2000K. I'm using Matlab R2011a.

Sorry about the long post and if it was somehow confusing,because there are a lot of details to give.
I can give my email if someone wants to help me!

Best Regards,
Luis

Link to download:
http://www.4shared.com/zip/EMgxOmwF/...ic_Nozzle.html

Anyone?!?!