Measurement and Calculation of the Expansion Parameters of Pulsed Plasma Jet in Air

To analyze the expansion characteristics of pulsed plasma jet in air, the expansion process of pulsed plasma jet was studied by a digital high-speed video system in this paper. The relationship of changes in the extended volume, axial displacement and radial displacement of pulsed plasma jet in atmosphere with time was obtained. A two-dimensional axisymmetric unsteady model for pulsed plasma jet expansion in air was established, and the numerical simulation of this process was conducted. The results demonstrate that the simulation values of axial expansion displacement of pulsed plasma jet are in good agreement with the experimental results. When the pulsed plasma jet is expanded, its shape is gradually extended from an initial ellipsoid shape to a shape with a conical head and an elongated cylindrical tail. The axial displacement of the jet is always larger than the radial displacement. The parameters of the jet field are distorted at the nozzle exit, with the occurrence of pulse decay occurring near the nozzle before it becomes increasing gradual and close to environmental parameters.