6.Levitan-1996-Electric fluctuation.pdf

IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 24, NO. 1, FEBRUARY 1996 137 Electric Fluctuations Caused by Gasdynamic Turbulence in Electric-Arc Devices Y. S. Levitan Abstract-Results of theoretical investigationson electric fluc- For small Joule _heating perturbations directed along the tuations in arc devices are presented. These electric fluctuations, current (for which j = const) for example, in electric arcs in gas flow and in serial MHD- generators, are caused by gasdynamic turbulence. Correlations giving the relationship between electric and gasdynamic fluctua- tions are obtained for these situations. Estimates of the influence of these correlations on the overall device parameters are given On the other hand, for the same perturbations directed perpen- here. dicularly to the current (for which E’ = const) + I. INTRODUCTION q:, = qv - (qv) = 032 - (.)E2 2 (a’/(.))(a)22. (3) HE appearance of 5lectric fluctuations (potential (p’, elec- Therefore, from (2) and (3) for a’/(c~) 0 Joule heating Ttric field strength E’, current densityj’l, Joule heating q;, perturbations decrease along the current direction and increase etc.) due to gasdynamic fluctuations (velocity G’, temperature perpendicularly. Small fluctuations of Joule heating are given T’, and pressure p’) is an important feature of electric- by arc devices with low temperature and mainly local th