Particle-in-cell - Technical Aspects

Technical Aspects

For many types of problems, the PIC method is relatively intuitive and straightforward to implement. This probably accounts for much of its success, particularly for plasma simulation, for which the method typically includes the following procedures:

• Integration of the equations of motion.
• Interpolation of charge and current source terms to the field mesh.
• Computation of the fields on mesh points.
• Interpolation of the fields from the mesh to the particle locations.

Models which include interactions of particles only through the average fields are called PM (particle-mesh). Those which include direct binary interactions are PP (particle-particle). Models with both types of interactions are called PP-PM or P3M.

Since the early days, it has been recognized that the PIC method is susceptible to error from so-called discrete particle noise. This error is statistical in nature, and today it remains less-well understood than for traditional fixed-grid methods, such as Eulerian or semi-Lagrangian schemes.