| dc.contributor.advisor | Bodenschatz, Eberhard Prof. Dr. | |
| dc.contributor.author | Capelo, Holly | |
| dc.date.accessioned | 2018-05-29T09:36:33Z | |
| dc.date.available | 2018-05-29T09:36:33Z | |
| dc.date.issued | 2018-05-29 | |
| dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-002E-E402-0 | |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-6863 | |
| dc.language.iso | eng | de |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | |
| dc.subject.ddc | 530 | de |
| dc.title | Dynamics of Suspended Dust Grains: Experimental Investigations and Implications for Protoplanetary Discs | de |
| dc.type | doctoralThesis | de |
| dc.contributor.referee | Bodenschatz, Eberhard Prof. Dr. | |
| dc.date.examination | 2017-10-16 | |
| dc.subject.gok | Physik (PPN621336750) | de |
| dc.description.abstracteng | The collective interaction of solid particulate matter with flowing
gas is one of the fundamental processes occurring in planet-forming
discs. Small dust grains and pebbles are comparable to or smaller than
the mean free path of the gas in observed and simulated discs, where
the collective force of particles on the gas has been predicted to
create a fluid 'streaming instability' that can produce a turbulent flow and associated
localised solid-density enhancements. Such fluid instabilities are therefore
favoured amongst candidate mechanisms that concentrate solids
in the initial stages of planet formation, which requires sufficiently
compact mass concentrations for gravity to play its role in assembling
matter, first by producing precursor planetesimals via gravitational
instabilities, and subsequently via accretion. Previously, the
streaming instability was studied analytically and with numerical
simulations. This is the first work to test the mechanism directly in
laboratory experiments. In this thesis, I show that the non-linear
phase of the streaming instability is manifest, both in experiments
and simulations, when fluidised particles settle against a
pressure gradient and the solid-to-gas density ratio is close to
unity. The experimental results set a precedent for empirical studies of scalable
two-phase flows with properties similar to the fluids in
protoplanetary discs. These experimental findings provide a test case to calibrate codes that include additional
physical processes important for mass assembly such as collisions and
charge attraction. Having established a facility to study low-pressure
gas flows will enable myriad additional tests of the dynamical interaction between
rarefied gas and sample materials. | de |
| dc.contributor.coReferee | Reiners, Ansgar Prof. Dr. | |
| dc.subject.eng | Hydrodynamics | de |
| dc.subject.eng | Instabilities | de |
| dc.subject.eng | Turbulence | de |
| dc.subject.eng | Methods: experimental | de |
| dc.subject.eng | Planets and satellites: formation | de |
| dc.subject.eng | Protoplanetary disks | de |
| dc.subject.eng | high Knudsen number flow | de |
| dc.identifier.urn | urn:nbn:de:gbv:7-11858/00-1735-0000-002E-E402-0-0 | |
| dc.affiliation.institute | Fakultät für Physik | de |
| dc.identifier.ppn | 1023449846 | |