QUASI-STATIONARY HEAT FLOW DIAGNOSTICS IN PLASMA JETS

摘要

The vortex structures in free plasma flow are identified using the information on the radiation intensity scanned in two mutually perpendicular directions by the CCD camera. Quasi-stationary regimes of free plasma flow are characterized by vortex structures in heat flows, noted for dynamical changes of the vorticity along the axis of the jet. The variant discussed in the paper makes it possible to identify the changes in dynamics by determining a three-dimensional course of the heat flow vector. The arrangement of the vortex structures generated by the vector potential is investigated considering a principal role of the product of enthalpy and flow velocity. The evolution of radiation intensity and dynamics of vortex structures in both the axial and radial direction about the jet's core is captured using the series of 8 shots within time interval of 100μsec. The analysis of vortex dynamics at flow rates 25slm and 40slm and electrical currents 150 A and 200 A is presented. To determine dynamics of vortex structures, we used algorithms of the MATLAB program, specifically the instructions 'streamline' and 'streamtube'. The presented results prove occurrence of several dynamic regimes of a vortex type in a quasi-stationary heat flow of free plasma flow, The occurrence and position of the vortex type regimes depends not only on flow rates of gas and on electric input but significantly also on the position of the diagnosed vortex structures towards the axis and orifice of the jet.