INVESTIGATION OF STRONG BLAST WAVES AND THE DYNAMICS OF LASER INDUCED PLASMAS IN HIGH PRESSURE GASES,
Abstract
Strong shocks produced when 2-3 joules of energy are released in high pressure gases by focusing a giant pulse laser are investigated analytically and experimentally. Strong blast wave theory is employed to calculate the position, velocity, maximum pressure, and temperature as functions of time and energy absorbed by the gas in the shocks formed for several gases at pressures of 1-2000 atmospheres. Experimentally, luminous fronts associated with strong blast waves produced in gases at pressures up to 2000 atmospheres with a focused 30 megawatt, 40 nanosecond pulse ruby laser are observed with Kerr cell photography. Optical interferometry with a Mach-Zehnder interferometer, absorption of a helium-neon laser beam, and piezoelectric pressure sensitive probe measurements of strong shocks produced in air at STP with a second, a 175 megawatt 17 nanosecond, giant pulse ruby laser show that during the rapid radial expansion of the shock, the measured position agrees to within 10% of that calculated. Relatively strong pressure fronts are observed at radii in excess of 50 cm and are spherical for radii larger than 2 cm. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0664589
Entities
People
- Arwin Adelbert Dougal
- Frederic Weigl
- Otto M. Friedrich Jr.
Organizations
- University of Texas at Austin