This benchmark is one of the classical free-convection density-driven flow and mass transport setups. It was originally published by Elder (1965) and has since then been used as a basic test case (Diersch & Kolditz, 1998; Guo & Langevin, 2002), or has been subject to various investigations concerning grid convergence (Graf & Degener, 2011) and numerical stability (Musuuza et al., 2009; Johannsen, 2003).
For the setup and parameterization, see the chapter “Density dependent flow - The Elder Problem” in Kolditz et al. (2012).
The Elder benchmark describes free convection of a dense fluid in mixable, single-phase environment. A high-concentration solute increases fluid density on the upper boundary and perpetrates the domain by evolving concentration fingers. Here, we compare numerical results of OGS-6 to those of OGS-5. Settings of both simulators were chosen to be as identical as possible. Simulation times were $3300 s$ and $7800 s$ for OGS-6 and OGS-5, respectively.
A comparison of the numerical data is shown in the figure below. The numerical results of OGS-6 coincide with those of OGS-5.Project file on GitLab
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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.
Musuuza, J.L., Attinger, S., Radu, F.A., 2009. An extended stability criterion for density-driven flows in homogeneous porous media. Adv. Water Resour. 32, 796–808. doi:10.1016/j.advwatres.2009.01.012.