Turbulence and Superstructures

BTU is part of a new priority program by the German Science Foundation DFG

BTU Cottbus–Senftenberg is taking part in a germanwide DFG priority programme once again. In the years 2007 to 2013, the Chair of Aerodynamics and Fluid Mechanics had already contributed to the DFG priority programme "Meteorology and Fluid Mechanics" under the direction of Prof. Dr.-Ing. Christoph Egbers with a reference experiment about baroclinic waves in the atmosphere. This year, the researchers are working on an experiment about turbulent pipe flow to deliver results for the new "Turbulence and Superstructures" priority programme. Under the management of Ilmenau University of Technology, 22 research teams from Germany, Switzerland and the Netherlands are studying the origin of superstructures and their significance for the turbulent transport of impulses and heat as part of the programme. "The results enable us to look into fully developed turbulent flows and to detect the expected large and very large scale structures in pipe flows", says the scientist.

The interest in organized, large-scale turbulent structures that generate large and very large motions has surged tremendously in recent years. But a solid definition of their character and an understanding of how they come about have remained elusive to this day. The new project is hence focussed on the nature and origin of these flows. Experiments and numerical simulations are very closely dovetailed. "With the help of the state of the art optical measurement techniques, we are able to map and research the expansive superstructures under controlled conditions in flow experiments inside our large pipe test facility, in cooperation with our international partners. I am really proud because we have constructed and built-up the pipe flow facility here at BTU from own funds over the last ten years", comments Egbers.

The "Cottbus Large Pipe Test Facility", or CoLa-Pipe for short, is one of four nationwide reference experiments in the new priority programme. The BTU facility has meanwhile become one of the world's largest of this nature, and became an important element of the European "EUHIT excellence network for the joint use of turbulence infrastructure facilities" in Europe. Other pipe flow experiments are located at Princeton University and the University of Bologna in Italy. To enable these fast and turbulent flows to be measured and visualized at all, the chair has been granted a fast flow measurement facility by the EFRE funding programme of the Land of Brandenburg, so that the work on the turbulent pipe flow in the priority programme is now all set to start. The interdisciplinary DFG priority programme SPP 1881 "Turbulent Superstructures" includes 22 sub-projects altogether. In the initial three-year stage of this interdisciplinary research programme, flow researchers, physicists, mathematicians and computer scientists from Germany, Switzerland and the Netherlands are cooperating under the management of the Ilmenau University of Technology. If the interim results prove a success in 2019, the programme will be extended by another three years.