Stokes effect on particle distribution in a circulating fluidized bed under swing motion

T. Zhaoa,b, M. Takeib, K. Liua, Y. Cuia

aFaculty of Mechanical and Precision Instrument Engineering, Xi`an University of Technology, China

b Division of Artificial Systems Science, Graduate School of Engineering, Chiba University, Japan

Abstract

In this present study, the electrical capacitance tomography technique, which can provide the real-time cross-sectional distribution of the flow component, was applied to visualize the distribution behaviors of desulfurization particles in the circulating fluidized bed under swing motion. A series of experiments were performed to investigate the effect of the swing motion on particle distribution. In these experiment the amplitude and period of the swing motion was maintained at ±0.2618 rad (±15deg) and 5s respectively. The limestone particle (group B) was used as the circulating particle. As results, the average particle volume fraction becomes smaller under swing motion due to the increase of the air-particle slip velocity. And the experimental results also show interesting dynamics of particle distribution behaviors that an obvious periodical variation of the particle volume fraction appears under swing motion due to the significant effect of stokes number, while this phenomenon did not appear under the upright condition in any previous literature.

Keywords: Circulating Fluidized bed; Swing motion; Electrical capacitance tomography; Stokes number