Experimental Investigation and Numerical Simulation on Interaction Process of Plasma Jet and working Medium

Abstract

The interaction between the plasma jet and medium has been applied in the field as aerospace and armament. In order to meet the requirement of the spacecraft’s orbital adjustment, gravitation compensate, position maintenance, orbital maneuver and the attitude control, many kinds of micro propulsion system, such as: micro electrical propulsion, micro cold air propulsion, micro laser propulsion, pulse plasma propulsion (Robert, 2003) and so on have been studied in many countries. The operation principle of the pulse plasma propulsion is as follows: the electric arc plasma forms by loading the electric energy at two ends of the capillary. The capillary plasmas with high temperature and pressure are then produced as the capillary wall can be burned by the electric arc. The plasma ejects out through the nozzle and pushes the chamber moving forward. In modern hypervelocity launching technique, the liquid propellant electrothermal-chemical technology (LPETC) is one of the effective one and develops well. The LPETC propulsion technology is a new propulsion technique to ignite the propellant by the high pressure and high temperature pulse plasma jet produced by capillary discharge. Accordingly, performance of the plasma jet and the interaction between the plasma jet and the medium (Nusca et al., 2001) is one of the key problems in plasma propulsion and the electrothermalchemical launching technique. Lots of works have been done according the related field by many scholars. Taylor M J studied the free expansion processes of the plasma in the atmosphere as the discharge energy is 30KJ (Taylor, 2001). The distributions of parameters as the temperature and pressure have been got. The free expansion characteristics of the plasma jet have been studied by Kim J U et al. as the discharge energy is 3.1KJ(Kim & Suk, 2002). The temperature and density distribution of plasma and the shock wave structure of the incompletion expansion jet have been got. The effects of discharge pulse length on the characteristics of plasma jet impacting the plate as the discharge energy is 3KJ has been studied by Lang-Mann Chang et al.(Chang, Harward, 2007). Guo H B et al. studied the discharge characteristics in the capillary (Guo, Liu, et al., 2007). Zhang Q et al. studied the expansion characteristics of the plasma jet in atmosphere as the discharge energy is less than 100J (Zhang et al., 2009). Wilsion D E et al. proposed the plasma jet axisymmetry unstable model (Wilsion & Kim, 1999). The plasma jet is treated as over expansion supersonic speed instantaneous jet and the development of expansion wave and Mach disc have been