negative density

March 15, 2005, 08:29

Hi All,

My run is coming out by giving -ve density error. The fluid is air with compressible setting on. In the geometry there is 0.9 mm gap through which air is flowing and pressure drop is around 5 bar. Is this the reason for -ve density error. My mesh is tetra and I have kept 3 cells in the 0.9 mm gap. I use MARS scheme.

Kindly guide.

Thanks

March 15, 2005, 10:27

you might try using UD scheme when starting from scratch and then move onto MARS discretisation scheme, it may help

-ted

March 15, 2005, 08:29	negative density	#1
novice Guest Posts: n/a	Hi All, My run is coming out by giving -ve density error. The fluid is air with compressible setting on. In the geometry there is 0.9 mm gap through which air is flowing and pressure drop is around 5 bar. Is this the reason for -ve density error. My mesh is tetra and I have kept 3 cells in the 0.9 mm gap. I use MARS scheme. Kindly guide. Thanks

March 15, 2005, 10:27	Re: negative density	#2
Ted Crilly Guest Posts: n/a	you might try using UD scheme when starting from scratch and then move onto MARS discretisation scheme, it may help -ted

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