[ffran]

Hi,
I have a relatively simple case to run: I have a simple periodic channel flow and I want to seed it with three clouds of Lagrangian particles (same material, different sizes) with one way coupling. However, I have seen that most of the solvers can only track one single kinematic cloud. Do you have any suggestions on how to go on, apart from running three different simulations?

Regards,
Francesco

[JulioPieri]

Hi Francesco, I had a similar problem recently and I managed to word around using swak4Foam. I was able to create multiple clouds by adding multiple 'injectionModels' to the kinematicCloudProperties file in constant folder.

Here is an example:

injectionModels
    {
        D1mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.7;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.001;
                }
            }

            flowRateProfile constant 0.1;
        }
        D2mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.6;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.002;
                }
            }

            flowRateProfile constant 0.1;
        }
        D3mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.5;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.003;
                }
            }

            flowRateProfile constant 0.1;
        }
}

I haven't tried this in native OF solvers, but I believe it might work as well.

[ffran]

Originally Posted by JulioPieri

Hi Francesco, I had a similar problem recently and I managed to word around using swak4Foam. I was able to create multiple clouds by adding multiple 'injectionModels' to the kinematicCloudProperties file in constant folder.

Here is an example:

injectionModels
    {
        D1mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.7;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.001;
                }
            }

            flowRateProfile constant 0.1;
        }
        D2mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.6;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.002;
                }
            }

            flowRateProfile constant 0.1;
        }
        D3mm
        {
            type            patchInjection;
            massTotal       0;
            parcelBasisType fixed;
            patch       outlet;
            nParticle       1;
            SOI             5.5;
            duration        0.1;
            U0              ( 0 0 -0.01 );
            parcelsPerSecond  400;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.003;
                }
            }

            flowRateProfile constant 0.1;
        }
}

I haven't tried this in native OF solvers, but I believe it might work as well.

Wow, sounds like a good idea, I will try!
How did you distinguish the different clouds in postprocessing? They have the same particle ID, right? Did you make the solver print the injectionModel in the outputs?

Francesco

[JulioPieri]

For my purpose, thresholding the diameter was enough. And yes, they had the same ID

[ffran]

I understand. Thank you very much for your help!

Francesco