Detta är ett uppsatsförslag hämtat från Nationella Exjobb-poolen. Klicka här för att komma tillbaka till samtliga exjobbsförslag.
Study of coagulation of microparticles under zero-gravity conditions
A highly efficient coagulation process of charged micro-particles was discovered during microgravity experiments in the International Space Station, ISS. Charged micro-spheres injected into a low pressure neutral gas environment form mm-sized aggregates, provided the initial number density is high enough. The coagulation occurred at a rate ~104 –105 times faster than that usually observed with uncharged grains. Theoretical estimates show that this process is so fast that it cannot even be explained by a coagulation process with charge enhanced cross-section. The observations can, however, be described by a gelation phase transition triggered by the dipole attraction between charged clusters.
Examples of large aggregates formed during the injection of microparticles into the neutral gas in experiment series 1. Typically, these large aggregates contain up to ~105 microparticles, or up to ~10% of the total particles injected.
After the pilot experiments with PKE-Nefedov, an extensive experimental campaign has been carried out in order to investigate these phenomena in-depth. Currently the data from this latter campaign are to be analysed. In the M Sci thesis offered here, detailed data analysis is to be performed with the goal to provide test for the original ideas.
Informationen om uppsatsförslag är hämtad från Nationella Exjobb-poolen.