Loading...

Time and space extended-particle in cell model for electromagnetic particle algorithms

Yazdanpanah, J ; Sharif University of Technology

1033 Viewed
  1. Type of Document: Article
  2. DOI: 10.1063/1.3695120
  3. Abstract:
  4. A general method for deriving electromagnetic particle in cell (EMPIC) algorithms has been given by Eastwood [Comput. Phys. Commun. 64, 252 (1991)]. This method devises variation of the action-integral to find discrete governing equations. The most important advantage of this method is automatic inclusion of the time coordinate via the action integral into the computational domain. This inclusion is inevitable because electromagnetic algorithms are based on time evolution of the system from its initial state. The drawback of this method is that it is rather abstract. This causes obscurity of particle-mesh interactions and makes it hard to analyze physical treatments of the computational model. This analysis is crucial both for finding error sources and for conformity of the computational model with the actual physical system. Errors are responsible for unphysical heating and/or cooling of the plasma. We have obtained EMPIC algorithms based on an objective model. This model consists of the shaped charged-particles. The particle shape has explicit time dependence as well as space dependence. Discrete field equations are obtained by appropriate integration of the actual continuous equations over a time-space mesh. The method of particle source assignment into the mesh has been derived by implying particle-charge conservation. The interaction of the shaped particles with self-consistent fields is briefly discussed. The effects of computational errors in unphysical behaviors of the system are studied. To show how theoretical results appear in application, results of a 2D PIC code in simulation of free expansion of collisionless plasma into a vacuum are presented
  5. Keywords:
  6. Action integrals ; Cell model ; Computational domains ; Computational error ; Computational model ; Electromagnetic particle ; Error sources ; Field equation ; General method ; Governing equations ; Initial state ; Objective models ; Particle shape ; Particle source ; Physical systems ; Physical treatments ; PIC codes ; Self-consistent field ; Shaped particles ; Theoretical result ; Time coordinates ; Time dependence ; Time evolutions ; Time-space ; Algorithms ; Computational methods ; Electromagnetism ; Errors ; Integral equations
  7. Source: Physics of Plasmas ; Volume 19, Issue 3 , 2012 ; 1070664X (ISSN)
  8. URL: http://scitation.aip.org/content/aip/journal/pop/19/3/10.1063/1.3695120