With a unique experiment that can only be carried out in weightlessness, BTU researchers from the Chair of Aerodynamics and Fluid Mechanics led by Prof. Dr.-Ing. Christoph Egbers want to investigate the effects of global warming on the Earth's polar caps and the associated changes in air and ocean circulation.
The DLR project AtmoFlow2: "AtmoFlow - Investigation of atmospheric flows in the spherical gap on the International Space Station (ISS)" started in February 2021. The funding period covers three years and a funding amount of approximately 500,000 euros.
After preliminary experiments - the preliminary stage AtmoFlow 1 ran from 2018 to 2020 - AtmoFlow2 will be the third time BTU technology and know-how will fly into orbit. Prof. Dr.-Ing. Christoph Egbers, Chair of Aerodynamics and Fluid Mechanics at BTU and head of the DLR-funded project is enthusiastic: "This is something completely special. There is hardly any other German university that has participated in so many space experiments for more than 20 years." These include numerous accompanying ground experiments and parabolic flights, during which weightlessness prevails for a short time.
Miniature Earth on the ISS
The main focus of the "Atmospherical Flow (AtmoFlow)" experiment is to study atmospheric convective flows in the spherical gap. Such spherical gap experiments are widely used and of central importance in the disciplines of geophysics, astrophysics and especially in atmospheric research. The special feature of the BTU technique is its spherical geometry in contrast to other often planar, Cartesian experiments. In AtmoFlow, flows in spherical geometry are to be studied under the influence of a central force field ("miniature Earth") subjected to atmospheric-like boundary conditions. This experimental setup cannot be realized on Earth because its gravitational field overlays the artificial central force field of the model. Under microgravity conditions, however, i.e., near-gravity conditions, the model force field can simulate convection - currents as they occur in the Earth's atmosphere, in the oceans, or in the magma mantle.
As things stand, the flight to the ISS is planned for 2024 or 2025. The goal of the BTU project is to establish a simulation model that calculates atmospheric convection processes based on data from the spherical model. By changing the boundary conditions - such as higher temperatures in the atmosphere - this model can also be used to simulate effects of climate change on flow processes and to approximate possible consequences.
Russia, the USA, Japan and Europe jointly operate the ISS and its research modules. From Germany alone, 40-50 experiments from various disciplines and institutions are running in the weightlessness of the space station.