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Old   March 27, 2005, 13:16
Default Second derivative
  #1
Thomas
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Hi cfx users,

Still don't manage to calculate d2u/dx2, which is equal to Velocity u.Gradient x.Gradient x Someone to help me?? Thanks,

Thomas
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Old   March 28, 2005, 12:02
Default Re: Second derivative
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liumalin
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can you explain you problem more detailed? calculate d2u/dx2 in the CFX-UDF? or in other place?
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Old   March 28, 2005, 13:38
Default Re: Second derivative
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Thomas
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Hey. I would like to calculate it with a Fortran routine and the command user_getvar. With that I'm able to obtain the gradient: so just velocity u.gradient.gradient (and not velocity u.gradient x.gradient x!!)... as I cannot use the variable created in cfx-post: velocity u.gradient x. Do you have any suggestion to calculate d2u/dx2?? It doesn't matter how. Thanks
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