Collaborative Research: Energy Conversion Beyond the First Law of Thermodynamics in Non-Equilibrium Plasmas

点击翻译按钮获取中文摘要

This award supports a collaborative effort at West Virginia University and the University of New Hampshire to study energy conversion in weakly collisional plasmas. One of the most challenging problems in the study of plasmas - gases hot enough that electrons come apart from the atoms - is understanding how energy is converted between electromagnetic fields and the thermal energy of the plasma, which is the energy associated with random motion of the electrically charged particles. This is an important problem across many types of plasmas, including plasmas in space and the very hot plasmas that are used in fusion energy development. These plasmas, where collisions between particles are very rare, are most often far from local thermodynamic equilibrium (LTE), which means that one cannot even define a temperature in the traditional sense. This project builds on a recent result quantifying energy conversion in non-LTE plasmas to perform the first systematic study of the non-LTE energy conversion in weakly collisional plasmas.The project will employ state-of-the-art particle-in-cell (PIC) simulations and satellite data from the Magnetospheric Multiscale (MMS) mission. Parametric simulations of two-dimensional magnetic reconnection and turbulence will be used to understand the dependence of thermal energy conversion on ambient plasma parameters. Secondary islands and flux ropes will be studied in two-dimensional and three-dimensional magnetic reconnection since they are known to be sites of particle acceleration and non-LTE dynamics. Finally, the theoretical formalism will be generalized to account for energy in both random motion and bulk motion and it will be used to study energy conversion in two-dimensional reconnection and turbulence. The project will directly contribute to the study of energy conversion in eruptive flares in the solar atmosphere, geomagnetic substorms that produce aurora and space weather impacts, and the heating of the solar wind; it will also set the stage for application in other areas of plasma science, including high energy density and fusion plasmas. The collaborative award is co-funded by the Plasma Physics program in the Division of Physics and the Magnetospheric Physics program in the Division of Atmospheric and Geospace Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.