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Old   March 15, 2011, 01:56
Default how to define user variables
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Wendy
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Hello everyone,

I want to write a user variable in CFX-pre for shear stress since there is only shear strain rate available in CFX-post:

Shear stress = shear strain rate x dynamic viscocity

Is there an example for that?

Thanks,

Wendy
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Old   March 15, 2011, 05:22
Default user variabels
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Matthias Finke
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Hi Wendy,

define your expression in CFX-Pre, after solving read in the result file in CFX-Post and define there a user scalar variable which references the expression defined in Pre.

best regards

Matthias
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Old   June 20, 2012, 15:40
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soni
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Hi matthias,

I would happy if you could tel me how we can make user defined variables in CFX post.

I would really appreciate.

Thanks
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Old   June 22, 2012, 04:32
Default user variable
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Matthias Finke
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Dear soni_sth,

for example if you are analyzing a pipe flow, you could add scalar or vector user definied variables into CFX-Post. For example i added "dynamic pressure"

- select "Variables" tab in CFX - Post
- right click into "Variables" white window
- select new or edit in command
- the data you want to use must be there, i mean a variable from solution or an expression defined in CFX - Pre

in the command edior your additional variable "dynamic pressure" should look like this:

USER SCALAR VARIABLE: dynamic pressure
Boundary Values = Conservative
Calculate Global Range = On
Expression = 0.5*Fluid.Density*(Fluid.Velocity)^2
Recipe = Expression
Variable to Copy = Pressure
Variable to Gradient = Pressure
END


hope this is what your are looking for,
best regards

MAtthias
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Old   June 22, 2012, 11:34
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soni
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Thanks a lot Matthias.
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