Single and multiple waves induced by power absorption
Abstract
Sub- and supersonic wave fronts produced by heat input have been generated in a shock tube driven by a step current pulse of variable magnitude (4-50 kA, duration up to 160 μsec). At high current and low fill gas densities, the supersonic mode appears and no substantial compression is possible. The limiting current Ic to reach this supersonic mode is determined as a function of the fill gas pressure. Front velocities, pressures, and electron densities are measured, and the heating characteristic (maximum enthalpy as function of the net absorbed energy flux) is derived. Scaling laws are obtained for the fluid parameters as a function of fill gas density and current. The measurements are interpreted in terms of one-dimensional wave model calculations. Studies with two stepped power pulse reveal that multiple shocks with a region of substantially increased density can be obtained only if the total current It remains below the critical value Ic. For It≳Ic, a supersonic heat wave is created after the transient phase, and multiple shocks with increased density can no longer be achieved.
- Publication:
-
Physics of Fluids
- Pub Date:
- February 1982
- DOI:
- 10.1063/1.863754
- Bibcode:
- 1982PhFl...25..247A
- Keywords:
-
- Electric Pulses;
- Energy Absorption;
- Heat Transfer;
- Plasma Waves;
- Shock Tubes;
- Detonation Waves;
- Laser Plasmas;
- Plasma Currents;
- Shock Wave Propagation;
- Subsonic Flow;
- Supersonic Flow;
- Wave Fronts;
- Fluid Mechanics and Heat Transfer