An electrothermal plasma model considering polyethylene and copper ablation based on ignition experiment

Abstract

In order to study the characteristics of electrothermal plasma interaction with energetic materials, especially the ignition ability, a novel model considering polyethylene and copper ablation is developed, and an ignition experiment system is set up. The parameters of the plasma and the surface conditions of the energetic materials are measured in the testing. The results show the measured first peak pressure to be ~2.2 MPa, the second peak pressure to be ~3.9 MPa, and the visible flame velocity to be ~2000 m s −1 . Circular pits of the order of microns and nanometers in size are observed on the surface of the energetic materials. Further, the parameters of the plasma, including static pressure, total pressure, density, temperature, velocity, copper concentration and PE concentration, are calculated and analyzed by the established model, under discharge currents of 9 kA. The simulation is similar to those of experimental results. A shock wave is observed in the experiment and is presented in the calculations; it plays an important role in the performance of the plasma in the nozzle region, where the parameters of the plasma variation trends are very complex. With the aim of obtaining the overall performance of the plasma, the coupling characteristics of multiple parameters must be taken into account, in accordance with the developed electrothermal plasma model.

Study of the enhanced burning rate during the plasma-propellant interaction process

“…The internal temperature distribution of the solid phase propellant is given by the solid phase heat transfer equation shown as equation (13).…”

“…Capillary discharge plasma has been found of great value in a variety of applications such as pulsed plasma thrusters [1], fusion reactor pellet injectors [2][3][4][5][6][7], and electrothermal chemical (ETC) launch devices [8][9][10][11][12][13]. In ETC launchers, the capillary discharge plasma is used to ignite the propellants, which has the advantages of a greatly-reduced and reproducible ignition delay, and a high adaptability to a wide range of ambient temperatures [14][15][16].…”

Investigation into geometric effect in capillary discharge plasma generator using an improved ablation model

“…They propose that the ablation mass of PE increases with the discharge current. In our previous work [20], we developed an electrothermal plasma model considering only the ablation of PE and copper, and the deposition and reevaporation processes of copper were not considered in the ablation model.…”

Effects of wire materials on radiative heat flux and spectral characteristics of a capillary discharge plasma jet

“…Based on Li's work, Hang et al has developed a 2D time-dependent capillary discharge model, showing that the radial variation of plasma characteristics is significant and is influenced by the ablation rate [26]. Zhang et al studied the interaction between the electrothermal plasma and energetic materials, investigating the effect of Cu vapor [27].…”