MODELING OF LONG STREAMERS IN ATMOSPHERIC-PRESSURE AIR

The undulatory propagation mechanisms of long streamers in a highly no nuniform electric field are considered, and the interrelations between main characteristics of the propagation process are clarified. The po tentialities of the streamer theoretical models are analyzed and the r esults of their applications are systematized. The necessity of solvin g a self-consistent problem, involving both the processes at the ioniz ation-wave front and in the channel behind the front, is shown. One-di mensional and quasi-two-dimensional streamer simulation models with a priori assigned constant channel radius are considered; their simulati on results are found out to depend critically on the channel radius. A hypothesis postulating the ionization mechanism of streamer channel e xpansion in the field of its own space-charge field, was developed and corroborated by computation results. The sensitivity of the computati on results to the rates of the elementary processes incorporated into the model was investigated in detail. The models involving detailed ki netics are shown to be sufficiently stable. This justifies the use of two-dimensional models of streamers in atmospheric air.