﻿ Dam-break problem with two types of liquids - XSim

# Dam-break problem with two types of liquids

Update: July 1, 2017
OpenFOAM 4.x

## Case directory

\$FOAM_TUTORIALS/multiphase/interMixingFoam/laminar/damBreak

## Summary

We calculate a dam-break problem with two types of liquids for 2 seconds. The calculation is performed as a 2-dimensional problem with a single mesh in the Z direction.

At initial state, the phase "water", "other", and "air" are arranged as shown in the figure below.

Model geometry

The physical properties of each phase "air", "other", and "water", as well as the interactions between the phases, are specified in the file "constant/transportProperties" as follows.

```phases (air other water);
air
{
transportModel  Newtonian;
nu              [0 2 -1 0 0 0 0] 1.48e-05;
rho             [1 -3 0 0 0 0 0] 1;
}
other
{
transportModel  Newtonian;
nu              [0 2 -1 0 0 0 0]  1e-6;
rho             [1 -3 0 0 0 0 0] 1010;
}
water
{
transportModel  Newtonian;
nu              [0 2 -1 0 0 0 0]  1e-6;
rho             [1 -3 0 0 0 0 0] 1000;
}

// Surface tension coefficient
sigma12           sigma12 [1 0 -2 0 0 0 0] 0.05;
sigma13           sigma13 [1 0 -2 0 0 0 0] 0.04;

// Diffusion coefficient between mixable phases
D23               D23   [0 2 -1 0 0 0 0]  3e-09;
```

The meshes are as follows, and the number of mesh is 2268.

Meshes

The calculation result is as follows.

Volume ratio of water (alpha.water)
Volume ratio of other (alpha.other)
Superposition of volume ratio of water (alpha.water) and other (alpha.other)
Volume ratio of water at 0.5 sec (alpha.water)
Volume ratio of other at 0.5 sec (alpha.other)

We can see that water and other are mixed.

## Commands

cp -r \$FOAM_TUTORIALS/multiphase/interMixingFoam/laminar/damBreak damBreak
cd damBreak

blockMesh

cp 0/alpha.air.orig 0/alpha.air
cp 0/alpha.other.orig 0/alpha.other
cp 0/alpha.water.orig 0/alpha.water

setFields
interMixingFoam

paraFoam

## Calculation time

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