Computation of flow patterns in circulating fluidized beds

✍ Scribed by Yuan P. Tsuo; D. Gidaspow

• Publisher: American Institute of Chemical Engineers
• Year: 1990
• Tongue: English
• Weight: 1022 KB
• Volume: 36
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690360610

✦ Synopsis

Computation of Flow Patterns in Circulating Fluidized Beds

Flow regimes of dense-phase vertical pneumatic transport of solids, referred to in the literature as circulating fluidized beds, have been computed using a generalization of the Navier-Stokes equations for two fluids. In the less dense regime corresponding to volume fractions of solids of about 1%, the flow consists of centrally upward moving solids and downward moving clusters. The computations agree with observations made by high-speed motion pictures and with measurements of radial solids concentrations and velocities. In the dense regime, corresponding to volume fractions of about 10%, a core-annulus type of regime is obtained, with solids descending down at the wall. The computed voidage distributions and velocity profiles agree with measurement done at the Institute of Gas Technology.