[sersunzo]

Hi everybody,

I try to figure out the use of directionMixed b.c.

I want a b.c. with the normal velocity =0 and the tangential velocity zeroGradient.
The way I understood the directionMixed is something like this

type directionMixed;
refValue uniform (0 0 0);
refGradient uniform (0 0 0);
valueFraction 1;
value uniform (0 0 0);

the refValue=uniform (0 0 0) means that I want a 0 normal velocity
the refGradient=uniform (0 0 0) means that I want a 0 gradient normal velocity
the valueFraction=1 means that the way I mix the two previous b.c (in my case only the first apply, if it were valueFraction=0 would be only the second)
The value=uniform (0 0 0) specify what to do with the gradient of the tangential component, no mixing this time only the gradient.

Thus I have three points
1) Is it correct my understanding?
2) There is a mistake somewhere, because the solver complains about the valueFraction 1; "Expected a '(' while reading VectorSpace<Form, Cmpt, nCmpt>, found on line 51 the label 1" Line 51 is valueFraction 1. But I do not understand what it is happening;why is it expected a '(' valueFraction is not a scalar?
3) There is another way for forcing a 0 normal velocity plus a zeroGradient tangential velocity?

Thanks in advance
Alessio