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April 12, 2010, 01:00 |
Mirror issue
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#1 |
New Member
Join Date: Feb 2010
Posts: 9
Rep Power: 16 |
Hello,
Im trying to get lift and drag of an airship which has symplified geometry to be an ellipsoid sphere. Now in cfx im getting a lift value for this object. However, im not suppose to obtain lift with same geometry for top and bottom surface and 0 AoA. It seems that the number of tetrahedrons for top and bottom surfaces were not exact (16060 to 16068) This gave me lift of ~180 N. I tried mirror option in cfx solution setup and it didn't work. I need assistance on setting up mirror options so that the object develops zero lift. |
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April 12, 2010, 18:23 |
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#2 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,700
Rep Power: 143 |
It will only give zero net force to numerical accuracy - what is your total force? If your solution is done properly this net lift force should be a fraction of a percent and can be ignored.
Mirror options? You mean symmetry planes? Have a look at the WB tutorials on the CFX community site (in the ANSYS webpage) for examples of how to set up symmetry planes. |
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