Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt

Down-Under by Bastian Knorr, IGÖ

In my graduate student project I investigate the influence of immobile water regions on the fate of contaminants in groundwater. It is supervised by Prof. Maloszewski, head of the Hydrological Modelling group, and co-supervised by Dr. Stumpp, head of the Hydrogeology group, at the Institute of Groundwater Ecology.

The outcomes of some of my laboratory column experiments were not what we expected and could not be described with our own analytical models to quantify the observed processes. It turned out that an additional process called density-driven unstable flow (i.e., free convection) occurred. This process was caused by a density contrast between two fluids. Since no one had worked on density-driven flow at our Institute so far, I contacted Prof. Craig Simmons who is based in Adelaide, Australia and is an internationally recognized expert in this field. I sent him some information about the project and inquired if he could host my visit at Flinders University in Adelaide, to set up a numerical model. As Craig Simmons was happy to do so and after receiving the HELENA Lab exchange grant, I went to Australia in March 2015, staying for ten weeks in total.

At the beginning, Prof. Simmon’s postdoc, Yueqing Xie, taught me how to use the numerical groundwater flow simulator FeFLow. I started working on the Elder problem, which is a famous 2D benchmark model for numerical simulations of free convection. After I gained some experience in FeFlow modelling and basic principles of density-driven flow, I started to set up a 3D numerical model to simulate my experimental results. Back in Munich, I am now able to use these results for the further work on my project. I am also still collaborating with Craig and Yueqing on additional topics that came up during my stay.

Besides my own work, I had the chance to participate in weekly program meetings with both internal and invited speakers. I enjoyed meeting graduate students from different scientific fields and having discussions during lunch or coffee breaks. Of course, there was also time to explore the sights of South Australia. Together with other visiting research students I went to places like Kangaroo Island, Flinders Ranges and the Adelaide Hills on the weekends.

Overall, my lab exchange was a great experience and I highly recommend it to everyone. I want to thank HELENA for the support, which made this collaboration with Flinders University possible. If you are about to plan your lab exchange, don’t hesitate to contact me if you have any questions.