[mahdi_izadi]

Dear colleagues
I have compiled a UDF in my case in serial mode, and then save it after some iteration and use it for parallel running.
The libudf folder has deleted.
Although All UDF equations are truly working but at reading case, It says auto compilation skipped no libudf found.

can it cause error?
regards

[pakk]

Yes it can cause big errors, your user defined function no longer work.
If you say "all UDF equations are truly working", I wonder what you mean. Fluent has no way to know which UDF equations you should have, so nothing should work.

[mahdi_izadi]

Originally Posted by pakk

Yes it can cause big errors, your user defined function no longer work.
If you say "all UDF equations are truly working", I wonder what you mean. Fluent has no way to know which UDF equations you should have, so nothing should work.

Dear Friend, pakk

Thanks for your answer.

udf includes 4 reaction.I mean reactions are happening, their heat of reaction and products are appearing(You mean the answer of product and Heat may change with or whitout LIBUDF-although it is getting solved)
I expect an equation to be or not to be! but changing with removal of UDF seems peculiar.

In fact I just have problem with interpolating mass fraction of species for changing mesh!
Regards

[pakk]

I believe you that your reactions are happening in the simulation. But I don't think any UDFs are used for the properties of those reactions.

I don't know which macro was in your udf, but possibly it was "DEFINE_VR_RATE". If you removed your udf, the equations in "DEFINE_VR_RATE" are not used, but Fluent uses the simpler constant rates. You will not see this as an extra warning or error, but you will just get wrong results.