Hello everybody, I try to set
 

Hello everybody,
I try to set up a new unsteady boundary condition by deriving it from the fixeValueFvPatchField, and I need to preserve some values between at least two time steps. For that I want to know how long such an object lives? Does it stay in memory between two time steps or I have to use some sort of "static" declaration for the variables I want to preserve?
Another question is that I want to enforce the usage of this boundary only for temperature fields. I suspect I have to use the dimensions for this but can anyone show me how to do that?

Thank you,
Dragos

The object lives as long as yo
 

The object lives as long as your time scheme. It will get renamed so after a ddt operation your old U becomes U_0 (and for second order time scheme U_0 will become U_00).

Just add a

Pout<< mesh.names()<< endl;

before and after a ddt operation and you'll see. (all objects are registered with the mesh and the 'names()' returns the names of these)

Thanks Mattijs, That is good
 

Thanks Mattijs,
That is good to know! But my concern was a litle bit different:
I have a class derived directly from fixedValueFvPatchField, and inside that class I define a member scalar. I was wondering if the value of that scalar is preserved from one iteration to another. Judging from your answer, I think yes!

Dragos