Accession Number:

ADA134691

Title:

Laser Diagnostic Development and Measurement and Modeling of Turbulent Flowfields of Jets and Wakes. Part 1. Two-Dimensional Laser Doppler Anemometer Studies of Isothermal Flowfield in a Ducted Centerbody Combustor.

Descriptive Note:

Final rept. 1 Apr 78-30 Sep 82,

Corporate Author:

DAYTON UNIV OH RESEARCH INST

Report Date:

1983-06-01

Pagination or Media Count:

139.0

Abstract:

A two-dimensional laser Doppler anemometer was designed to take measurements in a ducted coaxial flow system having a centerbody separating the jets. The measurements, made in isothermal flow, can be categorized as central jet only C02 annular jet only air and, combined central and annular jet flow. Radial profiles of the axial and radialazimuthal velocity were obtained. The central jet only condition approximates a free jet since the central jet diameter is much smaller than the centerbody or duct diameter 129.3 53.2. Measurements of the jet development diameter, turbulence intensity, etc. were compared with previous free jet studies. In a study of the isotropy of the turbulent fluctuations it was determined that fully developed turbulent flow begins further downstream than anticipated. Velocity profiles were combined with gas sampling measurements to ascertain jet entrainment. Results show a linear growth of the entrained mass starting at the entrance plane. Downstream 20 diameters the rate of growth increases to match past studies in that region. The annular jet flow creates a recirculation vortex in the wake of the centerbody. The flowfield was mapped and the streamlines describing the flow were obtained throughout the recirculating flow and further downstream.

Subject Categories:

  • Lasers and Masers
  • Test Facilities, Equipment and Methods
  • Fluid Mechanics
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE