Accession Number : ADP008906

Title :   A New Method for Directional LDA-Velocity Measurement of Lateral and Axial Components Using Diffraction Gratings,

Corporate Author : TECHNICAL UNIV OF LISBON (PORTUGAL)

Personal Author(s) : Mueller, H. ; Dopheide, D.

Report Date : 23 JUL 1992

Pagination or Media Count : 5

Abstract : Using diffraction gratings as beam splitters in LDA systems the resulting fringe spacing becomes achromatic. Thus employing unstabilized laser diodes of different wavelengths, distinguishable fringe systems with identical fringe spacings int he measuring volume can be generated. The evaluation of at least two LDA burst signals and their signal phase corresponding to the different fringe systems locally parallel shifted and/or tilted against each other allows the directional measurement of lateral and axial velocity components without using frequency shift techniques. Based upon the new techniques inexpensive and compact multicomponent LDA sensors for the directional measurement of lateral and axial velocity components can be realized. (Author)

Descriptors :   *LASER VELOCIMETERS, DOPPLER EFFECT, BEAM SPLITTING, GRATINGS(SPECTRA), DIFFRACTION ANALYSIS, GERMANY.

Subject Categories : Fluid Mechanics
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE