Accession Number:

ADA200558

Title:

Laser Thermal Propulsion

Descriptive Note:

Annual technical rept. 1 Sep 1987-31 Aug 1988

Corporate Author:

TENNESSEE UNIV SPACE INST TULLAHOMA

Personal Author(s):

Report Date:

1988-09-01

Pagination or Media Count:

4.0

Abstract:

The objective of this research investigation is to determine, experimentally and analytically, the physical mechanisms that determine the behavior of continuous and quasi-continuous, laser sustained plasmas LSP. The principal questions involve the effects of a forced convection environment, optical geometry and pulse format on the stability, fractional power absorption, plasma structure, and fluid mixing. The future application of this technology to space propulsion rests on the availability of lasers with powers in the megawatt range. It now appears likely that lasers of this size will be free electron lasers FEL that produce power as a series of pulses, rather than continuously. Transient argon plasmas were created using the 20 ns pulse from an excimer laser at a wavelength of 307 nm. These plasmas were self initiated from optical breakdown, requiring no auxiliary means for initiation as in the case for cw sustained plasmas. The decay of these plasmas were monitored using an optical multichannel analyzer OMA, and it was found that the plasmas decayed with microsecond time scales. Keywords Laser propulsion, Laser sustained plasmas, Plasma spectroscopy, Argon plasmas, Optical plasmotron, Free electron lasers.

Subject Categories:

  • Lasers and Masers
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE