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External Aerodynamic Simulation+negative densities

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Old   February 18, 2008, 04:51
Default External Aerodynamic Simulation+negative densities
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Ramkumar
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Hi all, I would like to know the following queries on STAR-CD:-

1) What boundary conditions on each face of the bounding box need to be given for simulating the aircraft encountering a large side-slip angle simultaneously with angle of attack.

2) When polyhedral cells are created and inviscid option is selected for solving, the solution diverged and the solver reported that the model got negative densities. I didn't understand what is meant by negative densities and why it is reporting like that.

I will be pleased if somebody answers the above questions as soon as possible.

thanks and regards, rvramkumar.
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Old   February 18, 2008, 16:27
Default Re: External Aerodynamic Simulation+negative densi
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ula
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it means you have bad polyhedral cells in your geometry. Try the same case but with the trimmer model.
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Old   February 19, 2008, 05:18
Default Re: External Aerodynamic Simulation+negative densi
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Ramkumar
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Thanks. I'll try with trimmer model. Nevertheless, When the mesh is checked, it was not giving any errors. Why this ambiguity?
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