Author_Institution :
Weapons Technol. Directorate, US Army Res. Lab., Aberdeen Proving Ground, MD, USA
Abstract :
Theoretical calculations are performed with a one-dimensional (1-D), steady state, isothermal computer plasma model to define plasma output parameters for various input electrical energies and capillary radii of relevance to the electrothermal-chemical (ETC) propulsion concept. Three capillaries of 1.92, 4.75, and 7.0 mm radius, and a fixed length of 11.84 cm, were chosen for this study with input currents between 30 and 350 kA. Plasmas are categorized according to their total power and energy levels (based on a 3-ms pulse width) and are compared with respect to their resistance, exit pressure, and core plasma temperature. The input power ranges from 0.17 to 1.89 GW, for input energies from 0.49 to 5.80 MJ, which is considered suitable coverage for ETC ignition through ETC enhanced propulsion concepts. The study shows that the range of resistance, pressure, and temperature are 12.8-195 mΩ, 19.8-2000 MPa, and 2.9-13.5 eV, respectively, for the chosen capillary geometry. Flow conditions for plasma calculations include choked (no pressure boundary) and unchoked (450-MPa pressure boundary) for some calculations. Results from the computational model and interpretations from the perspective of capillary implementation into ETC propulsion concepts are also included
Keywords :
electrothermal launchers; plasma devices; plasma flow; plasma pressure; plasma temperature; propulsion; 0.17 to 1.89 GW; 0.49 to 5.8 MJ; 1.92 mm; 11.84 cm; 12.8 to 195 mohm; 19.8 to 2000 MPa; 2.9 to 13.5 eV; 30 to 350 kA; 4.75 mm; 450 MPa; 7 mm; ETC ignition; capillary geometry; capillary implementation; capillary radii; choked flow; core plasma temperature; electrothermal-chemical propulsion applications; enhanced propulsion concept; exit pressure; flow conditions; high energy plasmas; input currents; input electrical energies; input energies; input power; isothermal computer plasma model; parametric study; plasma calculations; plasma output parameters; pressure; resistance; temperature; unchoked flow; Electrothermal effects; Energy states; Ignition; Isothermal processes; Parametric study; Plasma temperature; Propulsion; Space vector pulse width modulation; Steady-state; Temperature distribution;
