Cooling objects with sprinklers

Update: July 29, 2019
OpenFOAM 4.x

Case directory

$FOAM_TUTORIALS/lagrangian/reactingParcelFilmFoam/hotBoxes

Summary

We calculate sprayed water from two sprinklers onto boxes and a floor that are at a temperature of 300 K. the cooling of the boxes and the floor and evaporation of the water are calculated. We will calculate the water flow and the evaporation for 20 seconds.

Model geometry Model geometry

The properties of the discrete particles are defined in the file "reactingCloud1Properties" in the directory "constant". The liquid film model is defined in the file "surfaceFilmProperties" in the same directory.

The meshes are as follows.

Mesh Meshes
Meshes for the liquid film model Meshes for the liquid film model

The calculation result is as follows.

Discrete particles and temperature on the walls (T)

We can see that the wall temperature is dropping at the point where the water drops touch. Also, after the water spreads to the floor (time 1 second), the amount of water on the floor decreases due to evaporation (time 2 seconds).

Discrete particles and temperature on the walls at 0.1 (T) Discrete particles and temperature on the walls at 0.1 (T)
Discrete particles and temperature on the walls at 0.5 (T) Discrete particles and temperature on the walls at 0.5 (T)
Discrete particles and temperature on the walls at 1 (T) Discrete particles and temperature on the walls at 1 (T)
Discrete particles and temperature on the walls at 2 (T) Discrete particles and temperature on the walls at 2 (T)

The water/steam distribution in the cross section of the space is shown below. We can see how water/steam is distributed in the space by evaporation from the wall.

Water and steam 0.1 (H2O) Water and steam 0.1 (H2O)
Water and steam 0.5 (H2O) Water and steam 0.5 (H2O)
Water and steam 1 (H2O) Water and steam 1 (H2O)
Water and steam 2 (H2O) Water and steam 2 (H2O)

Commands

cp -r $FOAM_TUTORIALS/lagrangian/reactingParcelFilmFoam/hotBoxes hotBoxes
cd hotBoxes

cp -rf 0.orig 0

# create the underlying block mesh
blockMesh

# Make base meshes
topoSet

# Make boxes. Add the box patches to wallFilm patch.
subsetMesh c0 -patch wallFilm -overwrite
./patchifyObstacles

# Make liquid film model by extruding meshes
extrudeToRegionMesh -overwrite
changeDictionary

# Copy settings for liquid film model
rm -rf system/wallFilmRegion
cp -r system/wallFilmRegion.orig system/wallFilmRegion

find ./0 -maxdepth 1 -type f -exec sed -i -e "s/wallFilm/\"(region0_to.*)\"/g" {} \;

paraFoam -touch
paraFoam -touch -region wallFilmRegion

decomposePar -region wallFilmRegion
decomposePar

mpirun -np 4 reactingParcelFilmFoam -parallel

reconstructPar -region wallFilmRegion
reconstructPar

paraFoam

The mesh for the liquid film model is made by an extrude operation using the utility extrudeToRegionMesh.

Calculation time

7 hours 31 minutes 42.19 seconds *4 parallel, Inter(R) Core(TM) i7-2600 CPU @ 3.40GHz 3.40GHz