Pulse-Burst Cross-Correlation Doppler Global Velocimetry

An image-based flow velocimetry technique coupling pulse-burst laser technology and the cross-correlation Doppler global velocimetry (CC-DGV) technique is presented as a faster variant of the CC-DGV method. By scanning the laser frequency during the burst, the total scan time per velocity measurement can be reduced from 2-4 minutes (Cadel and Lowe, Optics and Lasers in Engineering, Vol. 71, Aug. 2015, pp. 51-61) to 10 ms, which is a speed increase of >1000 times. A demonstration of the technique has been performed in a 50 ms(-1) turbulent jet, where the accuracy and precision of the technique was determined to be 5 and 3 ms(-1), respectively, when compared with particle image velocimetry.