Hi everybody, what does elliptic mean?, what are elliptic(_staggered,_GCV,_colocated,...)?, thanks a lot

Elliptic refers to the form taken by the PDE's you're solving. It's the standard solver since it can handle recirculation (unlike the parabolic solver). Not sure what you mean by staggered, but GCV stands for general co-located velocity solver. What that means is that you solve cell centre velocities instead of cell face centre velocity. The GCV takes longer over it's sweeps, but converges quicker and is more robust than the standard solver for skewed BFC grids. Watch out though, when I last used PHOENICS, you couldn't restart a GCV solution and if you defined walls with negative conpor's, the walls got set wrong. I did tell CHAM, but I don't know if they've fixed it. You'll just have to set them the old fashioned way with patches. Hope this is of some help.