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May 4, 2010, 09:22 

#41 
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Rick
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May 4, 2010, 09:36 

#42 
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Jouke de Baar
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In the boundary condition panel you can set something like spin vector or spin axis orientation? If for example cd is in xdirection and spin axis is in ydirection (which you should check) then cl should be in zdirection.


May 4, 2010, 11:07 

#43 
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Rick
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I put an image of the orientation of the mesh attached
In the boundary condition for the ball: I have motion rotational and then a rotationaxis origin which I defined 0 for x,y,z and I have rotationaxis direction in which I have 0 for x,y and 1 for z. In the monitors I only have active the residuals, drag and lift. In the drag I have Force vector x=1 and in the lift I have force vector y=1, I think it's ok... 

May 4, 2010, 11:15 

#44 
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Jouke de Baar
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Yes that should be ok.
Hmmm ... this is strange ... Could you perhaps upload your case somewhere, such that I can have a look at it? 

June 15, 2010, 06:51 

#45 
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Rick
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June 15, 2010, 07:39 

#46 
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Jouke de Baar
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They are both correct.
However the upper definition is more conventional. This will give the correct force if you use the cl from FLUENT. Take care that A is the projected area of the sphere. ( \pi r^2 ) 

June 19, 2010, 18:37 

#47 
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Rick
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hello
I have another question, If you see the image I posted, it is a normal football where I did the analysis, I wanted to see more the edges and pattern, like this second image I found on the net can anyone help? best regards 

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