Accession Number:

ADA109060

Title:

Multiangular Scanning Absorption-Emission Techniques for Three Dimensional Combustion Diagnostics

Descriptive Note:

Annual rept. 1 Sep 80-30 Aug 81

Corporate Author:

GEORGE WASHINGTON UNIV WASHINGTON DC SCHOOL OF ENGINEERING AND APPLIED SCIENCE

Personal Author(s):

Report Date:

1981-12-01

Pagination or Media Count:

14.0

Abstract:

This program explores the potential of absorption techniques for low ppm, real time 3-dimensional combustion diagnostics. IN the current phase of activity, a laser beam has been transformed into a sheet of light and made to converge on a 126-element array, with electronics suitable for repeatable 1.5 KHz scanning and data processing. Available memory modules 4K allow for 34 successive slicings of a passing target within 20 milliseconds. In this manner, a detailed projection of three-dimensional flow field concentrations is available. An axisymmetrical flow tobacco smoke rings has been measured and a tomographic procedure was applied to these data. Better ranges of absorption are being considered and multiangular experiments non-symmetrical cases will follow. The construction of a portable tomographic unit is also in progress. It was upgraded to nonsteady flow capabilities by coupling a CAMAC digitizer with a MINC minicomputer. The source and sensor part of the experiment have been completed. Data processing and flow controls will follow. A theoretical review of flow instabilities is underway. Existing qualitative work suggests three- dimensional patterns for which this tomographic approach is ideally suited. Author

Subject Categories:

  • Optics
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE