What happens when you cough? How far does the air we breathe spread throughout a room? And does wearing a mask work? Amidst the Covid-19 pandemic, Prof. Dr.-Ing. Conrad Völker and his team – Dr.-Ing. Hayder Alsaad, Lia Becher and Amayu Wakoya Gena – are investigating these and other questions. 

Optical Schlieren Methods

Together with the help of two optical Schlieren methods – the unique Schlieren mirror and the Background Oriented Schlieren (BOS) – the Weimar scientists are able to make even the smallest air currents (invisible to the naked eye) visible. The Schlieren methods used in the department of Building Physics are primarily used to investigate indoor climates. With the outbreak of the coronavirus pandemic, however, completely new potential applications emerged.

»Our investigations focus on practical applications and researching potentially infectious breathing air using the examples of masks, respirators or, in cooperation with the Thuringian Philharmonic Orchestra Gotha-Eisenach, singing and playing music. Our goal is to contribute to the development of new hygiene and safety concepts«, explains Prof. Völker, project leader and Professor of Building Physics.

»Thüringer Forschungspreis 2021« Award 

The »Thüringer Forschungspreis« jury awarded this year’s prize in the »Angewandte Forschung« category to the research team at the Bauhaus-Universität Weimar and honours the scientific contributions of their most recent research work on »Optische Schlierenverfahren zur Visualisierung von Raumluftströmungen«.

»We have intensively researched the development of the two Schlieren methods over the past five years, currently through support from the Deutschen Forschungsgemeinschaft, and we are delighted that this work is being honoured with this research award. We plan to continue improving the Schlieren methods to increase the accuracy and informative value«, said Prof. Völker on winning the award. 

The »Thüringer Forschungspreis« is being awarded for the 21th time by the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft. The award will be virtually presented by the Minister of Science, Wolfgang Tiefensee. The awards ceremony along with videos and photos of all award winners in the »Grundlagenforschung« and »Angewandte Forschung« categories are available at www.thueringer-forschungspreis.de.

Measuring Methods Used

Schlieren methods (Schlieren mirrors and BOS) are optical methods for visualising and measuring indoor airflows. These methods visualise the differences in air density due to, in the cases of these studies, variations in temperature, pressure or humidity. Much like air that shimmers above the asphalt of an overheated street in summer, warm humid breathing air has a different density from the cooler room air. This difference in density leads to a deflection of light, which then appears as dark spots in a photo or video. These density differences, however, are extremely small in indoor airflows. They cannot be seen with the naked eye, but the Schlieren mirror allows them to be seen. There are currently only four large Schlieren systems in the world. Each one is used in a different research field.

The »Thüringer Forschungspreis«

The Free State of Thuringia has been recognizing top scientific achievements of Thuringian universities and research institutions with the »Thüringer Forschungspreis« once a year since 1995. Since then, more than 240 researchers have been honoured with the award. The reward recipients are decided by a jury of distinguished scientists from across Germany. The top achievements in basic and applied research by individuals or groups are awarded the »Forschungspreis« as well as a total of 50,000 euros in prize money.

Contact

Prof. Dr.-Ing. Conrad Völker
Bauhaus-Universität Weimar
Professorship of Building Physics

Phone: +49 (0) 36 43 / 58 47 01
E-mail: conrad.voelker[at]uni-weimar.de