From cc88a54a0ff3b1922670cb0e8ae4828946fc9cec Mon Sep 17 00:00:00 2001
From: Thomas Fischer <thomas.fischer@ufz.de>
Date: Fri, 2 Aug 2019 12:47:05 +0200
Subject: [PATCH] [webdocu] TimeDependentHeterogeneousParameter docu.

---
 ...geneousBoundaryConditionsAndSourceTerm.mp4 |  3 +
 ...source-term-and-boundary-conditions.pandoc | 84 +++++++++++++++++++
 2 files changed, 87 insertions(+)
 create mode 100644 web/content/docs/benchmarks/liquid-flow/TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4
 create mode 100644 web/content/docs/benchmarks/liquid-flow/time-dependent-heterogeneous-source-term-and-boundary-conditions.pandoc

diff --git a/web/content/docs/benchmarks/liquid-flow/TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4 b/web/content/docs/benchmarks/liquid-flow/TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4
new file mode 100644
index 00000000000..94489f2fa51
--- /dev/null
+++ b/web/content/docs/benchmarks/liquid-flow/TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:7a5a224e40a910789a0d8915e232ccd646efb6cd25edddcfbf97e9fa9a90b4f3
+size 486851
diff --git a/web/content/docs/benchmarks/liquid-flow/time-dependent-heterogeneous-source-term-and-boundary-conditions.pandoc b/web/content/docs/benchmarks/liquid-flow/time-dependent-heterogeneous-source-term-and-boundary-conditions.pandoc
new file mode 100644
index 00000000000..1fc33f8fa58
--- /dev/null
+++ b/web/content/docs/benchmarks/liquid-flow/time-dependent-heterogeneous-source-term-and-boundary-conditions.pandoc
@@ -0,0 +1,84 @@
++++
+date = "2019-08-02T11:33:45+01:00"
+title = "Liquid flow with time dependent boundary conditions and source term"
+weight = 171
+project = "Parabolic/LiquidFlow/TimeDependentHeterogeneousSourceTerm/TimeDependentHeterogeneousSourceTerm.prj"
+author = "Thomas Fischer"
+
+[menu]
+  [menu.benchmarks]
+    parent = "liquid-flow"
+
++++
+
+{{< data-link >}}
+
+## Motivation
+
+In real world examples the boundary conditions or source terms can vary over time
+and can be heterogeneous in space. This behaviour can be modelled using the
+TimeDependentHeterogeneousParameter for boundary conditions or source terms.
+
+## Specification in OGS project file
+
+In the parameter specification section of the project file it is possible to add
+a parameter type with the type `TimedependentHeterogeneousParameter`.
+```
+<parameter>
+    <name>ParameterForSourceTerm</name>
+    <type>TimeDependentHeterogeneousParameter</type>
+    <time_series>
+        <pair>
+            <time>0</time>
+            <parameter_name>parameter_for_timestep1</parameter_name>
+        </pair>
+        <pair>
+            <time>1</time>
+            <parameter_name>parameter_for_timestep2</parameter_name>
+        </pair>
+        ...
+        <pair>
+            <time>end_time</time>
+            <parameter_name>parameter_for_end_time</parameter_name>
+        </pair>
+    </time_series>
+</parameter>
+```
+Of course, the referenced parameters for the particular time steps have to be
+defined also. Values of the parameter are piecewise linear interpolated.
+
+
+## Example
+
+This simple example should demonstrate the use of the time depenendent
+heterogeneous parameter. We start with homogeneous parabolic problem:
+$$
+\begin{equation}
+s\; \frac{\partial p}{\partial t} + k\; \Delta p = q(t,x) \quad \text{in }\Omega
+\end{equation}
+$$
+w.r.t boundary conditions
+$$
+\eqalign{
+p(t, x) = g_D(t, x) &\quad \text{on }\Gamma_D,\cr
+k\;{\partial p(x) \over \partial n} = g_N(x) &\quad \text{on }\Gamma_N,
+}$$
+
+The example the domain $\Omega = [0,1]^2$ is a square. On the left
+($x=0$) side and the right ($x=1$) side time dependent Dirichlet-type boundary
+conditions are set. Until half of the simulation time high pressure values are
+set on the left side and low pressure values on the right side. In the second
+half of the simulation there are low pressure values on the left side and high
+pressure values on the right side. Additionally, the source term $q$ acts in
+the first quarter as a source, in the second quarter as a sink, in the third
+quarter as a source, and in the last quarter as a sink again.
+
+## Results
+
+<video width="838" height="762" controls>
+<source src="../TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4" type="video/mp4" />
+</video>
+<p>
+<strong>Download Video:</strong>
+<a href="../TimeDependentHeterogeneousBoundaryConditionsAndSourceTerm.mp4">"MP4"</a>
+</p>
-- 
GitLab