[yv3s95]

Hi,

I would like to make a list of parcels in MomentumCloud objects.
Basically, I want to populate a list (DynamicList) of parcels, which is stored for the whole iteration (injection of new parcels and cloud motion). Just for context, the list should contain parcels that are below a certain Zmin.

I am quite new to OpenFOAM development.

So first, how to create a new field in momentum clouds? This field should be a DynamicList of parcels.
Then, how to populate the list?

Here is what I tried to do.
In MomentumCloud.H, I added

void populate_parcels_of_interest(const double);
inline DynamicList<parcelType*> parcels_of_interest();
DynamicList<parcelType*> parcels_of_interest_;

In MomentumCloud.C, I added:

parcels_of_interest_(DynamicList<parcelType*>(0)),

in the constructor

template<class CloudType>
void Foam::MomentumCloud<CloudType>::populate_parcels_of_interest
(
    const scalar Z_min
)
{
    DynamicList<parcelType*>& parcels_of_interest = parcels_of_interest_;
    int i = 0;
    forAllConstIter(typename MomentumCloud<CloudType>, *this, pIter)
    {
        const parcelType p = pIter();
        scalar z = p.position().z();
        Info << "Pos: " << p.position() << nl;
        if (z < Z_min)
        {
            parcels_of_interest.append(&p);
            i ++;
            int j = 0;
            while  (j < i)
            {
                Info << "\tPos " << j << ": " << parcels_of_interest[j]->position() << nl;
                j++;
            }
        }
    }

    forAll(parcels_of_interest, i)
    {
        parcelType p = *parcels_of_interest[i];
        scalar z = p.position().z();
        Info << i << "-> Z_min: " << Z_min << " Z: " << z << " test: " << (z >= Z_min) << nl;
    }  
}

When I run the code for 1 step and look at the output (4 parcels injected):

Pos: (0.241657 -0.250083 0.395233)
        Pos 0: (0.241657 -0.250083 0.395233)
Pos: (-0.327668 -0.248501 0.42311)
        Pos 0: (-0.327668 -0.248501 0.42311)
        Pos 1: (-0.327668 -0.248501 0.42311)
Pos: (-0.49028 0.00792265 0.43253)
        Pos 0: (-0.49028 0.00792265 0.43253)
        Pos 1: (-0.49028 0.00792265 0.43253)
        Pos 2: (-0.49028 0.00792265 0.43253)
Pos: (-0.346966 -0.0428658 0.428971)
        Pos 0: (-0.346966 -0.0428658 0.428971)
        Pos 1: (-0.346966 -0.0428658 0.428971)
        Pos 2: (-0.346966 -0.0428658 0.428971)
        Pos 3: (-0.346966 -0.0428658 0.428971)
0-> Z_min: 1e+30 Z: 0.428971 test: 0
1-> Z_min: 1e+30 Z: 0.428971 test: 0
2-> Z_min: 1e+30 Z: 0.428971 test: 0
3-> Z_min: 1e+30 Z: 0.428971 test: 0

It seems like the element I add to the list is getting updated every time, instead of storing the parcel of interest.

I would greatly appreciate help on this matter, as I am really stuck on this problem to go forward in my project.

Thank you.

[olesen]

Since you have a DynamicList of pointers to your "particles of interest", it would be a bug if their values did not change. If you want a copy of their values, you can't be storing their pointers.