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[ICEM] What is the reason for this negative determinant?

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Old   January 25, 2013, 12:05
Default What is the reason for this negative determinant?
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Ye Zhang
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Hello,guys.

Now I want to simulate the flow over wind turbine rotor, but when I am doing the mesh, there is a problem that says negative determinant when I check the mesh. you can see the bad cells(green) in the picture. so I want to know what is the reason for negative determinant and how to improve the bad cells? Thank you in advance.

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Ye
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Old   January 25, 2013, 12:40
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Ghazlani M. Ali
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sometimes a simple update of the blocking can solve the problem.
best way to track those element is by using the scan edge or cut plane...
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New to ICEM CFD, try this document --> http://goo.gl/G2gkE
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Old   January 25, 2013, 13:28
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Hi, M.Ali

Thank you for your reply.
I can track(see)the bad cell, what I don't know is how to improve it? The green cells that have negative determinant looks quite triangle, right? but after the sharp trailing edge, I have get two blocks, is this the right method to deal with sharp edge?

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Ye
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Old   April 18, 2013, 09:59
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kiddmax have you found a way to sort this?

I'm having the exact same problem with a sharp edge.

The geometry and even the histogram look frighteningly similar too,,

Let me know.

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Old   April 18, 2013, 10:13
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Hi, Catthan

What about your blade? is it 3D or 2D?

I advice you to use C grid for the sharp trailing edge. This is a tutorial on youtube.
http://www.youtube.com/watch?v=mgjRT4WY_iA

and make sure to use a block for "boundary layer", that will be much better.
just like this
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Old   April 18, 2013, 10:15
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this is the picture
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Old   April 18, 2013, 10:59
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scan plane and cut plane are the best tools to look for thoe negative elements...
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New to ICEM CFD, try this document --> http://goo.gl/G2gkE
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