Frequency-modulated filtered Rayleigh scattering (FM-FRS) - A new technique for real-time velocimetry Conference Paper uri icon


  • © 1996 by J. H. Grinstead et al. Published by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. A new approach for a nonintrusive velocimetry diagnostic, which combines the sensitivity of frequency-modulated (FM) absorption spectroscopy techniques and the spectral discrimination afforded by filtered Rayleigh scattering (FRS), has been developed. Doppler-shifted light scattered from a flow is frequency-locked to an atomic vapor filter through closed-loop control of the probe laser frequency. The difference between the probe laser frequency and the filter transition is the Doppler shift. Preliminary experiments have established the viability of measuring FM absorption signals with light scattering. A computer simulation of the FM-FRS process has been used to examine the experimental conditions under which velocity measurements can be obtained. Issues such as accuracy, sensitivity, and sources of systematic error have been investigated.

author list (cited authors)

  • Grinstead, J., Finkelstein, N., Lempert, W., Miles, R., & Lavid, M.

citation count

  • 7

publication date

  • January 1996
  • January 1, 1996 11:11 AM