LDA Characterization of Coaxial Jets and Comparison with Other Measurement Techniques

The experimental aerodynamic characterization of a coaxial jet through LDA and hot-wire measurements is described. It is shown that, in the flow regions where the local level of turbulence is not excessive, the two techniques give similar results as regards the mean velocity and the statistical description of the turbulent components. Conversely, the time variations and spectra may be comparable only if adequate procedures are used for the acquisition and processing of the LDA signals. (Author)