A Compact Programmable Laser Doppler Velocimeter for Marine Applications

Abstract : The three major tasks conducted during this period are the completion of the construction of a small water test section, the testing of the electronic processor, and the successful acquisition of single and two-velocity component LDV data. The test section consists of a rectangular Plexiglass section with a nozzle on one end and an extraction orifice on the other. A recirculating pump and flexible tubing are used to draw water from a reservoir, flow it though the test section and return it to the reservoir. Polystyrene particles of 10 microns in diameter were seeded into the flow. The laser beams were oriented to measure both the horizontal and vertical velocity components. The test section could be oriented at arbitrary angles to the incoming laser beams to produce flows at arbitrary directions.