[waljoh]

Hello everybody,

I am working on a problem where I have to modify a field (drag) during run time. I already figured out that this is possible with manipulateField (swak4foam) and have a test case which is running in the right way:

 
test
{
    type manipulateField;
    mask "pos().x>5 && pos().x<6 && pos().y>0.5 && pos().y<0.7"; 
    expression "0.087+0.2*time()/100";
    fieldName drag;
    outputControl timeStep;
    outputInterval 1;
    writeManipulated true;
}

Now I would like to use a cellZone instead of the term in the mask line. Is that possible in a similar way to a swakExpression?

 
testenergy
{
    type swakExpression;
    valueType cellZone;
    zoneName testCellZone;
    variables "rho=1000;acell=20";
    expression "rho/2*drag*mag(U)*mag(U)*mag(U)*acell";
    accumulations (
        sum
    );
    verbose true;
    autoInterpolate true;
    warnAutoInterpolate false;
}

[andyru]

Hello,

I encountered the same problem.
Does anyone know the solution and wants to share it???

Many thanks in advance!

[andyru]

Hello,

I looked into swak4Foam and it is not so difficult to use cellZones.
Since manipulateField.C is marking cells with value 1 which have to be manipulated and all other cells are marked with value 0. one can programm it's own mymanipulateField.C/H and do the following.
Read in your cellZone

cellZoneExpression_(word(dict.lookup("zoneName")))

create an autoPtr conditionField:

autoPtr<volScalarField> conditionField_;

then
get the volScalarField with marked cells with the function call:

FieldValueExpressionDriver &driver=driver_();
        volScalarField &cField =conditionField_();
        cField = driver.makeCellZoneField(cellZoneExpression_);

since the function makeCellZoneField is already in FieldValueExpressionDriver

Hope, this helps for somebody who encounter the same problem.

Andy