Accession Number:

ADA165950

Title:

Techniques for Optical Interferanemography.

Descriptive Note:

Final rept. 15 Sep 83-16 Jun 85,

Corporate Author:

DAYTON UNIV OH RESEARCH INST

Personal Author(s):

Report Date:

1985-12-01

Pagination or Media Count:

120.0

Abstract:

The suitability of available anemometry and interferometry systems for forming an optical interfranemography system has been evaluated. It was determined that a three-dimensional laser Doppler interferometer LDA should be able to provide the spatial and velocity resolution required. All standard interferometric systems measure the integrated index variation along the line of sight. Consequently, they do not provide spatial resolution and are only adequate in systems that are symmetric along the line of sight. If spatial resolution is required, a tomographic system can be used but the optical access required exceeds that commonly available in wind tunnels. To overcome these shortcomings a new interferometric technique was searched for. It was found that the Lau interferometer could be modified so that measurements were made in a restricted volume. The interferometer that was assembled and tested operated in a shearing mode. The system used a white light source, yielding a bright image, and the system is able to withstand severe vibrations without degrading the signal. The Lau interferometer has been examined in detail and the theory of operation is presented. Keywords Optical interferanemography Laser Doppler anemometry Lau interferometry and flow diagnostics.

Subject Categories:

  • Lasers and Masers
  • Fluid Mechanics
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE