Implementation of neutralizing fields for particle–particle simulations using like charges

The particle–particle (PP) model has a growing number of applications in plasma simulations, because its high accuracy solving Coulomb collisions. One the main issues restricting practical use PP is large computational cost, which now becoming acceptable thanks to state-of-art parallel computing techniques. Another issue singularity that occurs when two particles are too close. most effective approach avoiding would be simulate with only like charges plus neutralizing field, such short-range collisions equivalent those using unlike charges. In this paper, we introduce way adding field by analytical solution electric domain filled uniformly distributed charges, for homogeneous and quasi-neutral plasmas under reflective boundary condition. Two common Cartesian geometries, cubic spherical, considered. verified comparing simulation results an electron–ion temperature relaxation problem, corresponding addition, it found can achieve significant speed-up 100 compared due capability larger time steps while maintaining same energy conservation.