Alignment technique for three-dimensional laser Doppler anemometry

Three-dimensional laser Doppler anemometry is a powerful, non-intrusive measurement technique. The high data rate point measurement allows direct quantification of turbulence quantities. However, for this type of study, a very high level of laser beam alignment is required; without good alignment only mean flow measurements are possible. We report here on an alignment procedure that is simple and cost-effective, yet results in much higher data rates than traditional, pinhole-based methods.