add docu of goswami benchmark

web/content/docs/benchmarks/hydro-component/goswami.md

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+author = "Marc Walther"
+weight = 142
+project = "Parabolic/ComponentTransport/goswami/"
+date = "2017-09-07T14:41:09+01:00"
+title = "Saturated Variable-Density Flow and Mass Transport"
+
+[menu]
+  [menu.benchmarks]
+    parent = "hydro-component"
+
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+
+{{< project-link >}}
+
+
+## Overview
+
+This benchmark features an Henry-like variable-density flow and transport setup that evaluates saltwater intrusion on laboratory scale. The original benchmark was published by Goswami & Clement (2007); OpenGeoSys5 has been verified for all steady and transient states of the original benchmark (see Kolditz et al., 2012).
+
+For the setup and parameterization, see the chapter "Density dependent flow - The Goswami Problem" in Kolditz et al. (2012).
+
+
+## Problem description
+
+The Goswami-Clement benchmark is based on experiment observations for intruding and receding saltwater in a laboratory-scale sand tank. Here, we compare numerical results of ogs6 to those of OGS5 and the original observation data.
+
+We had to extend the modeling domain to include the required boundary conditions on the left and right side.
+
+### Model results
+
+A comparison of numerical and laboratory data is shown in the figure below. The numerical results of ogs6 coincide with those of OGS5 and likewise with the laboratory observations.
+
+{{< img src="../goswami.png" title="Results for numerical (OGS5 - green, ogs6 - white) and laboratory data (black squares) together with concentration distribution in the domain and mesh resolution for steady state 1 (see original research paper).">}}
+
+[The project files are here. ](../../../../../Tests/Data/Parabolic/ComponentTransport/gosami)
+
+## Literature
+
+Goswami, R.R., Clement, T.P., 2007. Laboratory-scale investigation of saltwater intrusion dynamics. Water Resour. Res. 43, 1–11. doi:10.1029/2006WR005151.
+
+Kolditz, O., Görke, U.-J., Shao, H., Wang, W., 2012. Thermo-Hydro-Mechanical-Chemical Processes in Porous Media: Benchmarks and Examples, Lecture notes in computational science and engineering. Springer. ISBN: 3642271766.
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