AN EXPERIMENTAL AND NUMERICAL STUDY OF FLOW PATTERNS IN A CIRCULATINGFLUIDIZED-BED REACTOR

This paper presents an experimental and a numerical study on radial pr ofiles of axial particle velocity component in a cold how laboratory s cale circulating fluidized bed reactor. Laser Doppler anemometry (LDA) has been used to measure mean and root mean square (RMS) particle vel ocities for three different superficial gas velocities. A two dimensio nal two phase how model with a turbulent kinetic energy equation based on kinetic theory of granular flow is verified against the experiment al data. The model is based on a Eulerian description of the two phase s, gas and particles. The time averaged predictions are in good accord ance with the experiments. The model predicts a core annulus flow, sim ilar to that found experimentally. The predicted maximum velocity in t he core agrees well with the measurements, but the model overpredicts the downflow velocity near the wall. Calculated RMS velocity profiles are in good agreement with the experimental data. Copyright (C) 1996 E lsevier Science Ltd.