Update: September 29, 2018

$FOAM_TUTORIALS/lagrangian/reactingParcelFoam/verticalChannel

We calculate the flow in a channel that has 3 inlets and a single outlet for 0.5 s. Air flows in at 473 K from 2 side inlets and 573 K from the center inlet. The inflowing air is assumed to contain 1 % water (liquid). The Z-axis direction of the model is assumed to be a symmetrical plane, and the other walls are assumed to be no-slip walls. The negative direction of the Y-axis is assumed to be the gravity direction.

Model geometry (entire)

Model geometry (around inlets)

In the file "reactingCloud1Properties" in the directory "constant", We set the "phaseChangeModel liquidEvaporation" so that the water will evaporate.

In the file "controlDict" in the directory "system", the following settings are made to output the weighted average of volume the water and temperature at the region "outlet".

functions { surfaceRegion1 { type surfaceRegion; libs ("libfieldFunctionObjects.so"); writeControl writeTime; log yes; writeFields no; regionType patch; name outlet; operation weightedAverage; weightField phi; fields ( H2O T ); } }

The meshes are as follows, and the number of mesh is 93400.

Meshes on the inlet side

Meshes on the outlet side

The calculation results are as follows. All the results are at the final time.

We can see that as it flow through the channel, the water in the center channel where the temperature is higher, evaporates and takes away heat, increasing the (volume) ratio.

Temperature on the inlet side (T)

Temperature at 3-way junction (T)

Temperature on the outlet side (T)

Water on the inlet side (H2O)

Water at 3-way junction (H2O)

Water on the outlet side (H2O)

Air on the inlet side (air)

Air at 3-way junction (air)

Air on the outlet side (air)

The weighted average of water volume and temperature in the outlet region is as follows.

Weighted average of water volume at each calculation time (H2O)

Weighted average of temperature at each calculation time (T)

cp -r $FOAM_TUTORIALS/lagrangian/reactingParcelFoam/verticalChannel verticalChannel

cd verticalChannel

blockMesh

cp -r 0.orig 0

# Initialize with potentialFoam result

potentialFoam

rm -f 0/phi

reactingParcelFoam

paraFoam

gnuplot

gnuplot>plot "postProcessing/surfaceRegion1/0/surfaceRegion.dat" using 1:2 lc rgb "black"

gnuplot>plot "postProcessing/surfaceRegion1/0/surfaceRegion.dat" using 1:3 lc rgb "black"

cd verticalChannel

blockMesh

cp -r 0.orig 0

# Initialize with potentialFoam result

potentialFoam

rm -f 0/phi

reactingParcelFoam

paraFoam

gnuplot

gnuplot>plot "postProcessing/surfaceRegion1/0/surfaceRegion.dat" using 1:2 lc rgb "black"

gnuplot>plot "postProcessing/surfaceRegion1/0/surfaceRegion.dat" using 1:3 lc rgb "black"

- potentialFoam: 3.44 seconds
- reactingParcelFoam: 40 minutes 54.02 seconds

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