Developing a predictive understanding of plasma self-organization with application to natural and engineered plasmas Christopher Hansen Senior Research Scientist - University of Washington
Adjunct Associate Research Scientist - Columbia University Although uncommon on Earth, plasmas make up more than 99% of the visible matter in the universe and are pervasive in the near-Earth and interplanetary environments where spacecraft operate. In addition to their natural prevalence, the unique properties of plasmas, including their high energy density, tunable material properties and remote actuation via electromagnetic fields, make them desirable for a variety of engineering applications – such as electric propulsion and fusion energy. By virtue of a plasma’s ability to self-generate and interact with magnetic fields, topological constraints exist on the evolution of magnetized plasmas. These constraints arise from the conservation, on timescales longer than turbulent energy dissipation, of magnetic helicity and its more generalized forms. This separation of timescales leads to the nonlinear phenomena of plasma self-organization, through which plasma system tend to minimize their energy under a constraint of constant helicity. This talk will describe work by Dr. Hansen’s group to build a predictive understanding of plasma self-organization and other plasma phenomena through tightly- coupled experimental and theoretical investigations. Active projects to be discussed include: 1) experimental investigation of continuously-driven self-organized plasmas in the HIT-SI family of experiments [1,2], 2) the development of 3D multiphysics tools for predictive first-principles plasma modeling and design [3,4], and 3) the study of data-driven methods for building fast reduced-order models with application to real-time plasma control [5,6]. The goal of this work is to develop a hierarchy of tools that can be used to predict plasma behavior, for environmental and control applications, and to design engineered plasma systems that exploit self-organization and other unique plasma properties. This research program is supported by the US Department of Energy (Office of Science and ARPA-E), NSF and CTFusion. [1] A. Hossack et al., Nucl. Fusion 57, 076026 (2017)
[2] K. Morgan et al., Rev. Sci. Instrum. 92, 053530 (2021)
[3] C. Hansen at al., Phys. Plasmas 22, 042505 (2015)
[4] T. Benedett et al., Phys. Plasmas 27, 042508 (2020)
[5] A. Kaptanoglu et al., Phys. Rev. E 104, 015206 (2021)
[6] Y. Wei et al., Nucl. Fusion 61, 126063 (2021) Bio:
Chris Hansen grew up in the Seattle area before attending the University of Washington beginning in 2005. He graduated with a BS in Aeronautics & Astronautics from the UW in 2009 and again with a PhD on the topic of numerical plasma modeling from the UW in 2014. Since graduating, Chris has continued working as part of the A&A department first as a post-doc and then as research scientist where he now leads the HIT-SI lab and several other research projects. He currently lives in New York City where he also holds an adjunct position at Columbia University and collaborates with groups at Columbia and the Princeton Plasma Physics Laboratory. |