20090323048 | OPTICAL TRANSIT TIME VELOCIMETER - An L2F velocimeter comprises a probe for insertion into a fluid, the probe having an open area therein to allow the fluid to pass through. The probe comprises an illumination system to direct a pair of light beams, separated by a distance, through the open area, and a collection system to collect forward scattered light scattered from particles in the fluid. The collection system has an optical axis in common with the illumination system. The velocimeter further comprises an electro optical assembly connected to the probe to provide light to the illumination system, to receive light collected from the collection system, to measure a lapse time in fluctuations of the forward scattered light created by particles passing through the pair of light beams and to calculate the velocity of the fluid based on the lapse time and the separation distance. | 12-31-2009 |