Enhancement and Selectionaly Functional Control of Nonequilibrium Plasma Jet by Applying the Magnetic Field

点击翻译按钮获取中文摘要

Control of a non-equilibrium plasma jet by applying the magnetic field is investigated experimentally. The characteristics of plasma parameters, excited temperature and thermofluid characteristics are clarified under the different magnetic flux densities and under the magnetic field distributions of the mirror and the cusp types. With the increase of the magnetic flux density of the mirror-type, electron density, electron temperature and ion velocity increase rapidly, and furthermore, excited temperature, gas temperature and gas velocity increase slightly only in the core region. These may result from the confinement of electrons by magnetic lines of force, Lorentz force and the induced electric field effect. However, the cusp-type magnetic field shows a slight effect on the plasma characteristics, compared to the case of the mirror-type. This implies the mirror-type magnetic field is far better than the cusp-type for controlling the characteristics of a plasma jet. Seeding in the magnetic field is very effective to enhance the functionality of plasma jet.A three-fluid model is applied here for the numerical simulation of the axisymmetric flow and temperature fields in a nonequilibrium argon plasma jet which can be controlled by applying the electromagnetic field. The three-fluid model applied here can clarify the behavior of each plasma species. Equations of conservation for each plasma species coupled with the generalized Ohm's law, Maxwell's equations and the equation of state are simultaneously solved taking into account variable transport properties. It is shown that the electron temperature is the highest and the electron velocity is strongly influenced by the magnetic field. And the momentum and energy exchanges between plasma species can be changed by even small magnetic flux.