The aim of this exercise is to get familiar with the _DuMuX_ way of implementing new components (fluids) and fluid systems (mixtures). In the scope of this exercise, a new fictitious component is implemented (exercise _3a_) as well as its mixture with water (exercise _3b_).
The aim of this exercise is to get familiar with the _DuMuX_ way of implementing new components (fluids) and fluid systems (mixtures). In the scope of this exercise, a new fictitious component is implemented
(exercise-fluidsystem a) as well as its mixture with water (exercise-fluidsystem b).
## Problem set-up
The domain has a size of 60 x 60 m and contains two low-permeable lenses. Initially, the domain is fully water saturated and the fictitious component is injected through the middle portion of the upper boundary by means of a Neumann boundary condition. The remaining parts of the upper and the entire lower boundary are Neumann no-flow while on the two lateral sides Dirichlet boundary conditions are applied (hydrostatic conditions for the pressure and zero saturation).
## Preparing the exercise
* Navigate to the directory `dumux/tutorial/ex3`
* Navigate to the directory `dumux-course/exercises/exercise-fluidsystem`
### 1. Getting familiar with the code
Locate all the files you will need for this exercise
* The shared __main file__ : `exercise3.cc`
* The __input file__ for part a: `exercise3_a.input`
* The shared __main file__ : `exercise-fluidsystem.cc`
* The __input file__ for part a: `exercise-fluidsystem_a.input`
* The __problem file__ for part a: `2pproblem.hh`
* The __input file__ for part b: `exercise3_b.input`
* The __input file__ for part b: `exercise-fluidsystem_b.input`
* The __problem file__ for part b: `2p2cproblem.hh`
* The __spatial parameters file__: `spatialparams.hh`
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@@ -34,34 +35,39 @@ To see more components, fluidsystems and binarycoefficients implementations, hav
In the following, the basic steps required to set the desired fluid system are outlined. Here, this is done in the __problem file__, i.e. for this part of the exercise the code shown below is taken from the `2pproblem.hh` file.
In this part of the exercise we will consider a system consisting of two immiscible phases. Therefore, the _TypeTag_ for this problem (`ExerciseThreeBoxTwoPTypeTag`) derives from a base _TypeTag_ (`ExerciseThreeTwoPTypeTag`) that itself derives from the `TwoP` _TypeTag_ (immiscible two-phase model properties).
In this part of the exercise we will consider a system consisting of two immiscible phases. Therefore, the _TypeTag_ for this problem (`ExerciseFluidsystemTwoPTypeTag`) derives from
the `TwoP` _TypeTag_ (immiscible two-phase model properties) and the `BoxModel` _TypeTag_ (specifies properties of the discretization scheme).
In order to be able to derive from this _TypeTag_, the declaration of the `TwoP` _TypeTag_ has to be included. It can be found in the `2p/model.hh` header:
In order to be able to derive from these _TypeTags_, the declarations of the `TwoP` _TypeTag_ and `BoxModel` _TypeTag_ have to be included.
The `TwoP` _TypeTag_ can be found in the `2p/model.hh` header:
```c++
// The numerical model
#include<dumux/porousmediumflow/2p/model.hh>
```
Additionally, the _TypeTag_ for this problem (`ExerciseThreeBoxTwoPTypeTag`) derives from the `BoxModel` _TypeTag_, to specify properties of the discretization scheme. For a cell-centered scheme, you could derive from `CCTpfaModel` or `CCMpfaModel` instead. Again the corresponding header has to be included
while the `BoxModel` _TypeTag_ can be found in the `box/properties.hh` header:
```c++
// The discretization
#include<dumux/discretization/box/properties.hh>
```
As wetting phase we want to use water and we want to precompute tables on which the properties are then interpolated in order to save computational time. Thus, in a first step we have to include the following headers:
For a cell-centered scheme, you could derive from `CCTpfaModel` or `CCMpfaModel` instead (and, of course, include the right headers).
As one of the two phases we want to use water and we want to precompute tables on which the properties are then interpolated in order to save computational time. Thus, in a first step we have to include the following headers:
The non-wetting phase will be our new component, where we want to implement an incompressible and a compressible variant. The respective headers are prepared, but still incomplete. The compressible variant is still commented so that compilation does not fail when finishing the incompressible variant.
The other phase will be created from our new component, where we want to implement an incompressible and a compressible variant.
The respective headers are prepared, but still incomplete. The compressible variant is still commented so that compilation does not fail when finishing the incompressible variant.
```c++
// The components that will be created in this exercise
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@@ -82,26 +88,28 @@ This fluid system expects __phases__ as input and so far we have only included t
#include<dumux/material/fluidsystems/1pliquid.hh>
```
which creates a _liquid phase_ from a given component. Finally, using all of the included classes we set the fluid system property by choosing that the non-wetting phase is a one-phase liquid (OnePLiquid) consisting of the incompressible fictitious component and that the wetting-phase consists of tabulated water in the immiscible fluid system:
which creates a _liquid phase_ from a given component. Finally, using all of the included classes we set the fluid system property by choosing that
the water phase is liquid (OnePLiquid) and consists of the tabulated water component, and
the other phase is liquid as well and consists of the incompressible fictitious component. Both will make up the immiscible fluid system (TwoPImmiscible):
In order to do so, have a look at the files `dumux/material/components/base.hh` and `dumux/material/components/liquid.hh` to see how the interfaces are defined and overload them accordingly.
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@@ -137,14 +145,14 @@ In order to do so, have a look at the files `dumux/material/components/base.hh`
In order to execute the program, change to the build directory and compile and execute the program by typing
The saturation distribution of the nonwetting phase at the final simulation time should look like this:
The saturation distribution of the nonwetting phase S$`_n`$ (the phase consisting of our fictitious incompressible component) at the final simulation time should look like this:
