Laser Doppler Anemometry – a non‐intrusive optical measuring technique for fluid velocity

The present paper gives an introduction to laser Doppler anemometry. The fundamental principles of this measuring technique, as well as the basic features of its instrumental realizations, are explained. The application of laser Doppler anemometry to fluid investigations often requires an adaptation of the LDA‐system to the measuring problem. Basic formulas for the lay‐out and adaptation are given.