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 ar e described for an upward co-current gas-solids flow in a cylindrical vertical channel. Optical beams were used to measure particle velociti es along the chord lines employing a cross-correlation technique to ca lculate the mean particle velocity along the chord. The application of the technique is illustrated for gas-solid mixtures for different siz es of monodisperse particle sizes (100-1 500 mu m) and volume fraction s (0.002-0.02). This method provides an alternative to conventional la ser 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.