An Optical-Fiber Setup for Inert Particle Concentration Measurements

An optical-fiber setup employing laser light designed to measure concentrations of 50-to 500-μm particles moving with a speed of up to 10 m/s is described. The time resolution, the measurement time, and the counting of pulses reflected from the particles are programmed. The setup has the following basic parameters: time resolution is 10 μs, spatial resolution is 50 μm, sample size is up to 32 × 103, and particle counting error is within 1%. The setup was applied to measurement of the solid-phase concentration in a two-phase flow in a volum concentration range of up to 30%.