A study of stability and energy conservation of a 3-D electromagnetic PIC code for non-orthogonal meshes

Summary form only given. A 3-D electromagnetic particle-in-cell code (EMPIC) was developed for large-scale plasma simulation on parallel computers. To simulate plasma problems with complex geometries such as high-power microwave generation devices, curvilinear coordinates were used. A logically connected cartesian grid consisted of hexahedral cells that could be deformed to body-fit complex shapes. A finite-volume method for a non-orthogonal grid was used to calculate the electromagnetic field. This method is based on Gedney-Lansing (1995) and Madsen (1995) algorithms, and is reduced to a standard FDTD algorithm for an orthogonal grid. Particle updates use current deposit formulation of Villasenor and Buneman (1992) generalized to non-orthogonal meshes, preserving charge and current. The stability of the entire code and of the electromagnetic algorithm in particular was analyzed on non-orthogonal meshes. Questions of how the code stability and energy conservation are influenced by numerical mesh distortion are addressed. Ways of improving the code stability and accuracy are discussed.