||September 6, 2013 03:54
No. I've explained it several times before: differential operators can only be calculated for the whole field at once and I don't want to trigger a calculation on thousands (millions) of cells just to update a few hundred faces, If a user wants that he should create that field with an expressionField-functionObject (curlU for instance) and then use it in his BC. Only downside is that this only happens at the end of the time-step. So for a solver that does several loops per timestep it might be inaccurate. But if it is for a patchExpression, swakExpression it shouldn't be a problem
Thanks for your reply bernhard, although I have looked for it and find nothing!!
In fact, I meant calculate the curl(U) by using functionObjects. So, if I try to calculate the curl(U) just in the patch I get this error:
--> FOAM FATAL ERROR:
Parser Error for driver PatchValueExpressionDriver at "1.1-4" :"field curl not existing or of wrong type"
I assume you mean calculate and store the curl(U) in the volume by means of an expressionField and then use the stored e.g. 'curlU' in the expression within the patchExpresion, isn't it?? In this way it works though I was not very sure of being right.
On the other hand, for a surface integral on a patch, always by using swakExpressions, should I use 'mag(Sf())' as 'dS' term as in the volume one I use 'vol()' as 'dV'??
Thank you very much!