7. Phase-Doppler technique

The aim of phase-Doppler anemometry is to measure the speed and size of individual particles in situ in a flow. In principle, this method requires no calibration.

This paragraph is divided into three sub-paragraphs:

• the first is dedicated to presenting the principle of the technique;

• the second takes a closer look at the effect of trajectory ambiguity, due to the finite lateral extension of laser beams;

• the third describes the extensions currently being developed for this technique, which exploit the finite aspect of laser beams.