Model of High-Pressure Ablative Capillary Discharge for Plasma Thrusters with Capillary Wall Thermal Conduction and Radiation Absorption (Preprint)

摘要

A zero-dimensional time-dependent high-pressure slab capillary discharge model with capillary wall thermal conduction and radiation absorption is presented. The model includes a resistor-inductor-capacitor circuit and a heat-transfer radiation model based on a radiation database constructed using PrismSPEC, a commercially available radiation software, to calculate the radiation heat flux output from a uniform plasma slab. The model also includes a model of the thin transition boundary layer between the uniform plasma core and the ablative capillary walls. This transition boundary layer model is used to obtain the boundary conditions connecting the plasma core parameters with the parameters at the ablative surface to calculate the thermal and radiation heat fluxes at the capillary walls. The radiation wall absorption coefficient is assumed to be a constant independent of wavelength and wall temperature and is an input parameter of the model. The wall thermal conductivity is also assumed to be a constant independent of the wall temperature. Thus, the model self-consistently calculates plasma parameters of the capillary discharge and distribution of wall temperature vs. time. The model is used to model high- pressure ablative capillary discharge for plasma thrusters.