Fractal characteristics of electrical discharges: experiments and simulation

It has been demonstrated that the general topological characteristics of branched electrical discharges can be efficiently described by the concept of fractal geometry. However, researches carried out on this subject hitherto have been restricted to computer simulation of discharge patterns without reference to experimental data and physical discharge mechanisms. In the work, therefore, a specific discharge type is studied, namely a Lichtenberg figure in SF6, for which experimental results are presented together with a discussion of the underlying physical processes and numerical simulations. Good agreement is found between experiment and simulation and it is shown that the approximate fractal scaling of the discharge figure is a consequence of specific underlying physical mechanisms.