MEASUREMENT OF PARTICLE-VELOCITY DISTRIBUTION IN A VERTICAL CHANNEL

Experimental measurements of particle velocity as a function of radial position using a novel arrangement of non-intrusive optical probes are described for an upward co-current gas-solids flow in a cylindrical vertical channel. Optical beams were used to measure particle velocities along the chord lines employing a cross-correlation technique to calculate the mean particle velocity along the chord. The application of the technique is illustrated for gas-solid mixtures for different sizes of monodisperse particle sizes (100-1 500 mu m) and volume fractions (0.002-0.02). This method provides an alternative to conventional laser Doppler anemometry (LDA) instrumentation for measurement in dilute gas/solid mixtures and, unlike LDA, enables the velocity field within the entire cross-section to be measured simultaneously.