Award Date
5-1-2022
Degree Type
Thesis
Degree Name
Master of Science (MS)
Department
Physics and Astronomy
First Committee Member
Zhaohuan Zhu
Second Committee Member
Chao-Chin Yang
Third Committee Member
Jason Steffen
Fourth Committee Member
Rebecca Martin
Fifth Committee Member
Pengtao Sun
Number of Pages
45
Abstract
The radial pressure gradient (RPG), along the midplane of gaseous protoplanetary disks (PPD) – planetary nurseries – poses a severe obstacle to planet formation. Micron-sized dust grains, embedded in the disc, must quickly grow to kilometer-sized planetesimals – the building blocks of planets – before fatally drifting inwards, by RPG-induced gas drag, into a central host star. However, the RPG simultaneously powers one of the most robust processes to overcome this radial-drift barrier: the streaming instability (SI). Spontaneously triggered, the SI aerodynamically concentrates drifting dust via drag-induced, coupled interactions and feedback with the surrounding gas. In particular, the non-linear phase of the SI has not been rigorously or thoroughly studied in the presence of different RPGs, despite implications and expectations from linear analysis. Thus, we numerically simulate and analyse the non-linear evolution of the SI among various RPGs in unstratified, 2D shearing sheets, corotating with the disc, using the Athena++ code, extended to include Lagrangian particles with feedback to the gas. Depending on particle size and initial dust concentration, we find that different RPGs noticeably affect the non-linear growth, saturation, structure, and resultant dust density distributions of the SI, the details of which are not obvious nor expected from linear analysis. Our results offer many new, valuable insights into the complexity of dust-gas dynamics as well as implications for both planet formation theories and PPD observations.
Keywords
asteroids comets Kuiper belt objects; computational fluid dynamics; hydrodynamics; instabilities; simulations; turbulence
Disciplines
Astrophysics and Astronomy | Other Physics | Physics
File Format
File Size
2200 KB
Degree Grantor
University of Nevada, Las Vegas
Language
English
Repository Citation
Baronett, Stanley Antedio, "Dust-Gas Dynamics Driven By the Streaming Instability with Various Pressure Gradients" (2022). UNLV Theses, Dissertations, Professional Papers, and Capstones. 4360.
http://dx.doi.org/10.34917/31813237
Rights
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