Prof. Dr. Yassin A. Hassan

Prof. Dr. Christian J. Kähler

James T. Heineck

University of the Federal Armed Forces 

NASA Ames Research Center

The importance of turbulence in preventing airborne infections

Airborne Schlieren: Developments for Imaging X-59 QueSST

Presentation Single and multiphase flow investigations in nuclear reactor cores are important to characterize thermal hydraulic responses in nuclear fuel assemblies. Nuclear reactor assemblies often consist of complex geometries where the opacity of the fuel elements pose limitations to investigate internal velocimetry characteristics. The implementation of flow visualizations using the matched-index-of-refraction (MIR) based particle image velocimetry (PIV) allows a quantification of several fluidics parameters overcoming the complexities – critical toward the safety and optimization of nuclear reactor designs. The next generation of nuclear reactor designs, Generation IV, consist of several innovative nuclear reactor designs (LMFR, GFR, PBR, etc.) The high-fidelity PIV data for such nuclear fuel assemblies significantly assist in the development and validation of computational fluid dynamics models.

Presentation The pandemic has shown everyone that dealing with the threat of the virus is associated with high costs for society. It is therefore in people's interest to develop methods that enable a normal life even when a virus threatens us again. The formation, release, spread, inhalation, and deposition of the droplets and aerosol particles that can transmit viruses from person to person are fundamental problems in fluid mechanics. Fortunately, we have powerful measurement techniques to analyze these phenomena in detail. The lecture will show how we can gain very valuable qualitative and quantitative information about the relevant flow problems with simple experiments. Furthermore, it is shown how practical protection concepts and rules of conduct can be derived from the scientific findings. The latest research results show that a very differentiated approach is appropriate, since physical stress and the age of the people have a major impact. 

Presentation NASA Armstrong has led the effort to capture high-fidelity schlieren imagery of the shock X-59 QueSST Low-boom Flight Demonstrator. This aircraft will fly at 15,200 m (50,000 ft) and produce a sonic “thump” that is much quieter than the sonic booms aircraft produced to date. Three techniques were developed: Airborne Background Oriented Schlieren, Background Oriented Schlieren using Celestial Objects, and Sun-limb distortion schlieren. Each method was developed to provide complementary capabilities and addressed different engineering issues encountered with deployment. The history of these developments and the current design of the imaging system for the QueSST campaign will be discussed.

Biography     Prof. Dr. Hassan is a Professor of Nuclear Engineering and Mechanical Engineering at Texas A&M University. He is the director of the new Center for Advanced Small Modular and Micro Nuclear Reactors and runs the Thermal-Hydraulic Research Laboratory at Texas A&M. His research interests lie in hydrogen production and nuclear technologies, as well as in fluid mechanics, turbulence and laser velocimetry and imaging techniques. He is a fellow of the American Association for the Advancement of Science, the American Society of Mechanical Engineers and American Nuclear Society (ANS). He was awarded numerous awards in fields of mechanical and nuclear engineering. In 2007, Hassan was sworn in as a part-time technical judge to the Atomic Safety and Licensing Board Panel of the U.S. Nuclear Regulatory Commission.

Biography     Prof. Dr. Kähler is Professor for Fluid Dynamics and director of the Institute of Fluid Mechanics and Aerodynamics of the University der Bundeswehr (Munich). His research covers a broad range of topics, such as the development of optical measurement techniques (PIV, PSP) to investigate complex phenomena from microfluidics to aerodynamics and turbulence. He is associate editor of Experiments in Fluids (Springer Nature) and author of the 3^rd edition of the Particle Image Velocimetry practical guide. His expertise is much recognized, and he is often present in the national media and worldwide. He acts frequently as scientific advisor of numerous government institutions in Germany, and he has chaired and organized many flow visualization conferences and workshops worldwide.

Biography    JT Heineck has been a scientific imaging specialist for more than 25 years at NASA Ames Research Center. During this time, he has developed and applied several trailblazing flow visualization techniques, such as Retroreflective Focusing Schlieren, Doppler Global Velocimetry, Stereoscopic PIV and many others. His long collaboration with Markus Raffel (who is a Master Class Lecturer for the MFV) had him working with BOS methods since 2001. He has developed and applied thermography techniques for boundary layer transition measurements since 2012 and demonstrated the applicability for helicopter rotor measurements during wind tunnel and flight testing. He holds four US Patents, received a NASA Exceptional Engineering Achievement Medal, AIAA Ground Test Award, and is an Associate Fellow in the AIAA.