Spatial effects of an electrically generated plasma on the interior ballistics of electrothermal-chemical (ETC) guns

Electrothermal tapered capillary hyper jet focused-injection plasma source concept

“…Elecrothermal capillary discharges used in most ETC experiments were cylindrical with an average length of 9-15cm and average diameter 4-10mm, and either operating in the ablation-controlled confined arc regime or fused with a thin aluminum wire as an exploding fuse to initiate the discharge [2], [3], [5], [8]- [11]. Pulse length varies between 0.1-1.0ms with discharge currents in the range of few kA to 100s kA, and can provide plasma pressure of several 100MPa, exit plasma velocities of up to 5km/s and greater, and plasma temperature in the range of 10,000-40,000 o K [3][4][5][6][7][8][9][10][11][12][13]. Modeling of these capillaries was either in 0-D or 1-D based on the assumption that the plasma temperature distribution is constant along the radius of the capillary [4]- [15].…”

Two-phase flow simulation of plasma-ignited combustion in an energetic fluid bed

“…Electrothermal plasmas are of interest for applications in areas such as rocket propulsion, electrothermal-chemical launchers and hypersonic mass acceleration technology [1][2][3][4]. Recent experimental and theoretical research efforts have focused on the use of plasma to optimize and control solid propellant ignition and combustion processes in an energetic fluid bed.…”

“…One of the most promising propulsion concepts based on the use of a plasma source is the Solid Propellant Electrothermal Chemical launching Technology (SPETC) [5]. However, the prediction of its performance by lumped parameter models, based on the assumption that propellant grains and the products of combustion constitute a well-stirred mixture, has been difficult as electrical energy density increases [2]; therefore, agreement with experimental results has been poor. It should be noted that it is indeed possible to obtain a good agreement with experimental chamber pressure history in a solid propellant electrothermal firing by significantly over-estimating the muzzle velocity.…”