Modeling a signal generated by microparticles moving in the aerodynamic flow

2019;
: pp. 173–178
https://doi.org/10.23939/mmc2019.02.173
Received: April 21, 2019
Revised: October 01, 2019
Accepted: October 01, 2019
1
National Aviation University
2
National Aviation University

The article presents a model of a signal generated by microparticles moving in an aerodynamic flow.  This model is based on the Lorentz–Mie scattering theory.  It is shown that the visibility and the signal/noise ratio of the Doppler signal are determined by the degree of amplitude and polarization matching of the scattered waves.  These parameters also depend on the degree of phase matching of "elementary" Doppler signals.  Using this signal model, it is possible to calculate the shape of the aperture of the receiving optics for a specific type of laser Doppler anemometer.  The use of such an aperture will increase the visibility, the signal-to-noise ratio and the measurement accuracy of the aerodynamic flow velocity using a laser Doppler anemometer.

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Mathematical Modeling and Computing, Vol. 6, No. 2, pp. 173–178 (2019)