Development of a Granular Matter Experiment Device for X-Ray Radiography in Microgravity

Kurzfassung

Graunular matter is an important subject in applications and everyday live. Examples of granular matter that people come into contact with in daily life are sand, snow, powders or breakfast cerals. However, fundamental knowledge on granular matter is poor in contrast to knowledge about solid matter and fluids. Due to this, granular matter physics is an important topic of current research. Two main subjects of investigation are particle dissipation (cooling) and segregation in an agitated granular medium. Gravity has a signifuicant influence on segregation and dissipation processes so it is important to also conduct investigations under 0-g conditions. Since optical systems can only observe the surface of a granular medium, X-ray technology has been used to investigate granular matter since the 60's. However, granular materials have never been observed using X-ray technology under 0-g conditons. The DLR institute of Materials Physics in Space developed a radiography device using for parabolic flights. This device offers to observe granular matter using X-ray technology under µg conditions for the first time. For this purpose an experiment was developed to observe dissipation and segregation processes of granular samples during a compaction process. This compaction process was realized using a sample cell with two pistons that can change the volume of the cell. The experiment was performed as a part of the 22nd. DLR parabolic flight campaign in April 2013. The development of the granular matter experiment as well as the implementation of pretests is the topic of this master thesis. This includes the development of an analysis procedure and the design of a fluidized bed.