Different results from zeroGradient and groovyBC/codedMixed
 

Hi everyone,

I'm working on urban CFD modelling, using OpenFoam v6, and I want to implement custum bondaries conditions to :
-implement temperature and velocity profiles
-change the condition according to wind direction

I already code two solution working either on groovyBC or codedMixed perfectly running on simple case.

My problem is relate to converge issue. It appears that for some reasons, at large scale solution doesnt not coverge in temperature.

After running some simple test case, it seems that for the first iterations zerogradient from codedMixed and groovyBC not work as expected.

In other word, solution converge if I implement :
{
type zeroGradient; (or fixedGradient)
}

and doesnt not coverge if I implement either :

type groovyBC;
valueExpression "T_air(time())";
gradientExpression "0";
fractionExpression "0";
value uniform 300;
either :

type mixed;
refValue 300.0;
refGradient 0;
valueFraction 0;

Stop my if I'm wrong but it supposed to perform the same things... Any ideas ?