Spraying water into a channel with a filter

Update: September 25, 2018
OpenFOAM 4.x

Case directory

$FOAM_TUTORIALS/lagrangian/reactingParcelFoam/filter

Summary

We suppose a two-dimensional model geometry of a channel with a filter, as shown in the figure below, and calculate the flow in the channel for 5 seconds. Air (79% nitrogen, 21% oxygen) flows in from the region "inlet" at a velocity of 5 m/s and a temperature of 350 K. The temperature of the channel wall is 400 K.

In addition, water flows in for 1 second at the 4 "injections" on the inlet side and for 2 seconds at the "source" on the outlet side. On the inlet side, water flows in in the form of particles for calculation.

Model geometry Model geometry

The filter is configured in the file "fvOptions" in the directory "constant" by defining the cell zone "filter" as a porous body as follows.

		
filter1
{
    type            explicitPorositySource;
    active          yes;

    explicitPorositySourceCoeffs
    {
        selectionMode   cellZone;
        cellZone        filter;

        type            DarcyForchheimer;

        DarcyForchheimerCoeffs
        {
            d   (500000 -1000 -1000);
            f   (0 0 0);

            coordinateSystem
            {
                type    cartesian;
                origin  (0 0 0);
                coordinateRotation
                {
                    type    axesRotation;
                    e1  (1 0 0);
                    e2  (0 1 0);
                }
            }
        }
    }
}		

The properties of the particles are defined in the file "reactingCloud1Properties" in the directory "constant". However, the inflow position and other properties are defined in the file "parcelInjectionProperties" in the same directory, as shown below, and are set by referencing this file in "reactingCloud1Properties".

// (x y z) (u v w) d rho mDot T Cp (Y0..Y2) (Yg0..YgN) (Yl0..YlN) (Ys0..YsN)
(
    (0.1 0.32 0.0) (0.5  0.25 0.0) 0.001 1000 0.2 300 4200 (0 1 0) () (1) ()
    (0.1 0.44 0.0) (0.5  0.10 0.0) 0.001 1000 0.2 300 4200 (0 1 0) () (1) ()
    (0.1 0.56 0.0) (0.5 -0.10 0.0) 0.001 1000 0.2 300 4200 (0 1 0) () (1) ()
    (0.1 0.68 0.0) (0.5 -0.25 0.0) 0.001 1000 0.2 300 4200 (0 1 0) () (1) ()
);

To make meshes, we make meshes with blockMesh at first. Then, topoSet is used to define the cell zones and face zones for the channel inlet, filter, and channel outlet, and createBaffles is used to create the inner faces that should be the boundaries between the channel and filter from the face zones.

The meshes are as follows, and the number of mesh is 1720.

Mesh Meshes

The calculation result is as follows.

Water (H2O)

The motion of the calculated particles is shown below. The color of the particles represent their velocity.

Calculated particles at 0.8 sec Calculated particles at 0.8 sec
Calculated particles at 1.5 sec Calculated particles at 1.5 sec
Calculated particles at 2 sec Calculated particles at 2 sec
Calculated particles at 3 sec Calculated particles at 3 sec
Calculated particles at 5 sec Calculated particles at 5 sec

Commands

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

blockMesh
topoSet
createBaffles -overwrite

reactingParcelFoam

paraFoam

Calculation time

1 minutes 7.42 seconds *Single, Inter(R) Core(TM) i7-2600 CPU @ 3.40GHz 3.40GHz