Estimation of particulate velocity components in pneumatic transport using pixel based correlation with dual plane ECT

This article presents a technique developed to estimate the velocity components of two phase solid/gas flow using electrical capacitance tomography (ECT). The pixel by pixel correlation method for consecutive frames in a given sensor plane has been used to trace the particle velocity profile in the transverse direction. The transverse movement of solid particles in slug flows has been reported recently in the literature. The transverse velocity of the particles is probably caused by the picking up mechanism experienced by single particles, to form a slug body. Rest of the particles following the slug forms a stationary layer thus exhibiting no transverse component. These phenomena have also been observed in earlier studies using high-speed video camera. The pixel-based correlation using ECT confirms these observations and also helps to detect the slugging phenomena. The same technique is implemented to trace the path of rotational motion of an object inside the sensor plane and also to detect the transverse motion of particulates in dilute phase vertical pneumatic conveying system. Both axial and transverse velocity components estimated by ECT are verified using Laser Doppler Anemometer (LDA). (C) 2006 Elsevier B.V. All rights reserved.