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By means of a self-consistent three-dimensional particle model of the sourceextraction transition region of a surface-produced negative ion source, the characteristics of negative ion transport have been revealed. It is purely electrostatic and collision-induced (charge exchange with atoms) and magnetic-induced (gyration around filter field) transport contributions play no relevant role for the H− transport. In fact, the key point is the penetration of the EG field inside the source, which helps removing negative ions produced on the surface. This study suggests that the best PG shape is characterized such to allow the extraction EG field from attaching the surface from where H− are produced and that the best aperture size is directly related to this particular shape.

The work concerns the simulation of negative ion formation and acceleration in a radio‐frequency discharge for neutral beam injection system for ITER, with particular emphasis on the IPP negative ion source. To generate intense beams of negative ions and to optimize the negative ion source, understanding of transport properties of negative ions H− is indispensable. To study this effect, we have developed a 1D(z)‐3V Particle‐in‐Cell electrostatic model of the production and extraction regions. The motion of charged particles (e, H+, H2+ and H−) in their self‐consistent electric field and of neutral particles (H(n=1,2,3) and H2(X1Σg+, ν=0,…,14)) is simulated. Surface and volumetric processes involving plasma and neutral systems have been included by using different Monte Carlo Collision methods. Comparisons between numerical and experimental results have been done in order to validate the code.

We present here an account on the progress of kinetic simulation of non equilibrium plasmas in conditions of interest for negative ion production by using the 1D Bari code for hydrogen plasma simulation. The model includes the state to state kinetics of the vibrational level population of hydrogen molecules, plus a PIC/MCC module for the multispecies dynamics of charged particles. In particular we present new results for the modeling of two issues of great interest: the time filtering and the Cs addition via surface coverage.

We present a 1D(r)2D(v) particle code for capacitively coupled radio frequency discharge plasmas in hydrogen, which includes a rigorous kinetic modeling of ion transport and several solutions to speed up the convergence. In a test case the effect of surface atom recombination and molecule vibrational deactivation on H− concentration is investigated.

Non‐Maxwellian behaviour and plasma‐wall interaction are key processes in the physics of Hall thrusters. For this purpose, a 2D{r,z}‐3V axisymmetric fully kinetic Particle‐in‐Cell/Monte Carlo Collision (PIC‐MCC) model of the acceleration channel including the process of secondary electron emission (SEE) from the dielectric walls has been developed. In order to make the simulation possible with regard to the computational time, a reduction of the thruster dimension was done. This was derived from a new physics‐based scaling law. This model has demonstrated its outstanding capability in improving the physics insight into the processes in Stationary Plasma Thruster (SPT) and in reproducing accurately well experimental data.

We study the dynamics of a steady overdriven detonation wave in planar geometry by means of DSMC simulation. The exothermic reaction is modeled as a single step, irreversible, threshold reaction with Arrhenius kinetics. Results show that the nonequilibrium character of the velocity distribution function in the shock front modifies substantially the kinetics of the reaction and the overall profile of the reaction zone.

Self‐consistent models for homogeneous and one dimensional DC and RF discharges are illustrated for different chemical systems. In particular the coupling between vibrational kinetics, electronic kinetics and Boltzmann equation for the electron energy distribution function is illustrated in the case of nitrogen plasmas. Different self‐consistent models including the homogeneous solution of Boltzmann equation, fluid model and PIC‐MCC (particle in cell with Monte Carlo collisions) are then used for understanding RF discharges. In all cases it is emphasized the role of the coupling between heavy particle kinetics and free electrons dynamics.