Time Characterization of High Density Gas Jet from a Pulsed Supersonic Nozzle via Laser Produced Plasma

【摘要】 <正> A high-density gas jet supersonic nozzle is reported in this paper.The jitter andactuation time of the nozzle is determined by the pin discharge and laser spark radiation respec-tively.The jitter time of the nozzle is within 10 μs with the backing pressure as high as 25 bar.With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle,the actuationtime is calculated to be about 15 ms by detecting the laser produced spark radiation,which revealsthe existence of the gas jet and the relative gas density evolving with time.Consequently the gasdensity is estimated to be well above 10¹⁹ cm^-3,compared with theoretical simulations from thenozzle parameters.更多还原

【Abstract】 A high-density gas jet supersonic nozzle is reported in this paper.The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respec- tively.The jitter time of the nozzle is within 10 μs with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle,the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation,which reveals the existence of the gas jet and the relative gas density evolving with time.Consequently the gas density is estimated to be well above 10¹⁹ cm^-3,compared with theoretical simulations from the nozzle parameters.更多还原