Injection of water droplets into the flow channel

Update: September 29, 2018
OpenFOAM 4.x

Case directory

$FOAM_TUTORIALS/lagrangian/reactingParcelFoam/parcelInBox

Summary

We suppose the model geometry as shown in the figure below and calculate the flow for 0.5 seconds. Air containing 1 % water flows in from the region "inlet" at a velocity of 1×10-8 m/s and a temperature of 473 K. The region "wall" is a no-slip adiabatic wall and depth direction walls are set to symmetry condition.

And a water droplet is set at position "droplet".

Model geometry Model geometry

The water droplet is defined in the file "reactingCloud1Properties" in the directory "constant".

		
subModels
{
    particleForces
    {
        sphereDrag;
        gravity;
    }
    injectionModels
    {
        model1
        {
            type            manualInjection;
            massTotal       5.23599e-10; // 1 droplet of density 1000 kg/m3
            parcelBasisType mass;
            SOI             0;
            positionsFile   "reactingCloud1Positions";
            U0              (0 0 0);
            sizeDistribution
            {
                type uniform;
                uniformDistribution
                {
                    minValue        100e-06;
                    maxValue        100e-06;
                }
            }
        }
    }
    dispersionModel none;
    patchInteractionModel standardWallInteraction;
    heatTransferModel RanzMarshall;
    compositionModel singleMixtureFraction;
    phaseChangeModel liquidEvaporation;
    devolatilisationModel none;
    surfaceReactionModel none;
    stochasticCollisionModel none;
    surfaceFilmModel none;
    radiation       off;
    standardWallInteractionCoeffs
    {
        type            rebound;
    }
    RanzMarshallCoeffs
    {
        BirdCorrection  off;
    }
    singleMixtureFractionCoeffs
    {
        phases
        (
            gas
            {
            }
            liquid
            {
                H2O 1;
            }
            solid
            {
            }
        );
        YGasTot0        0;
        YLiquidTot0     1;
        YSolidTot0      0;
    }
    liquidEvaporationCoeffs
    {
        enthalpyTransfer enthalpyDifference; // latentHeat;
        activeLiquids   ( H2O );
    }
}	

The "reactingCloud1Positions" referred to here means the file "reactingCloud1Positions" in the directory "constant", which defines the initial positions of the water droplet.

The meshes are as follows.

Mesh Meshes

The calculation results are as follows. The effect of water droplets does not appear in the flow because the effect of water particles is very small and the calculation time is short.

Flow velocity at final time (U) Flow velocity at final time (U)
Water at final time (H2O) Water at final time (H2O)

Also, as we can see from the files "positions" and "U" in the directory "lagrangian/reactingCloud1" in each time result directory (0.1~0.5), the calculated particles motion is very small during the calculation, although the calculation is being well done.

Commands

cp -r $FOAM_TUTORIALS/lagrangian/reactingParcelFoam/parcelInBox parcelInBox
cd parcelInBox

blockMesh
reactingParcelFoam

paraFoam

Calculation time

2.16 seconds *Single, Inter(R) Core(TM) i7-2600 CPU @ 3.40GHz 3.40GHz