[Gianmario28]

Dear all,

I'm working with Fluent and I need to create the expression to use the custom variable (ex.xxx).

But when I define my variable the following an error message appear: "WARNING 'Vertex' values for Variable 'xxx' do not exist on Geometry /DATA READER/CASE:Case case_file_name/BOUNDARY:desired-surface. ". this error is due to the following expression: Temperature^4-298.15^4.

How I can fix it?

Thanks

[LutfiFauzi]

Try to write Temperature - 10 or anyting else and the same error will come. I encouter same problem with you.

It just will fine if Temperature*2 or anyting except + and -.

[LutfiFauzi]

Did you have solve your problem? I'm still confuse

[EMorse]

Originally Posted by LutfiFauzi

Try to write Temperature - 10 or anyting else and the same error will come. I encouter same problem with you.

It just will fine if Temperature*2 or anyting except + and -.

Try to write Temperature - 10[K], 10 is dimensionless.

[Kinder]

Hello there,

Might be a little late but in case someone needs this : I had the same issue with a user-defined variable on CFD-Post and the reason I had that warning is because in a specific area of my geometry, the variable went to an infinite value. The denominator of the variable was 1-Z (Z being another variable, the mixture fraction, which is between 0 and 1) and in order to not reach infinity, I simply wrote 1.00001-Z at the denominator instead in my user defined-variable. That solved the problem very well without making a significant difference to my results.

Cheers!