Modeling the physics of interaction of high-pressure arcs with their electrodes: advances and challenges

Incorporation of realistic models of plasma-electrode interaction remains a bottleneck in the development of predictive models of devices with high-pressure arcs. The most important aspects of the underlying physics have already been understood, so no fundamentally new physical mechanisms have been described in the recent publications (which are many); the aim was rather to develop practicable numerical models that adequately describe known mechanisms. Unfortunately, no universally accepted numerical models have emerged: the developed models are in many cases incompatible with each other and it is not easy to identify the place of each model in the global picture. The aim of this contribution is to summarize physically justified descriptions of the interaction of high-pressure arcs with their electrodes and to survey from this point of view the recent works, thus bringing them into a kind of system as possible. The relevant aspects of the conventional LTE arc models are discussed. Outstanding challenges for future work are identified.