Extending PIC Models to Higher Pressures—Enhanced Model of Collisions

This paper treats the problems of the particle-in-cell (PIC) models at higher pressures. We discuss the influence of the time discretization on the results of a model of a highly collisional plasma using a simplified analytical model. A new algorithm is proposed that calculates the collisions independently of the simulation time step, thus eliminating the errors introduced by the time discretization. The benchmarks at the pressure of the neutral gas of 665 Pa show that the presented algorithm is approximately seven times faster than a classical PIC model with the same accuracy.