Backscatter Laser Velocimeter for Energetic Deep-Sea Flows: Performance Study in Particulate Dense Water

A dual beam backscatter laser Doppler velocimeter designed for oceanographic usage will be described. The instrument was constructed to test, in the laboratory, the signal characteristics as a function of suspended particle loading in the water - a subject of concern in the study of high energy benthic boundary layers. It has been found that with proper design, the predominant mode of signal observed is still from the single scatterer, at particle concentrations of up to 5 mg/ℓ. Variations in signal-to-noise ratio will be described and compared with theoretical calculations.