Force characteristic of a large dense object in a fluidized bed equipped with an inclined air distributor

• Inhomogeneity of transverse gas–solid flow in bottom bed with inclined distributor is revealed.
• Instantaneous characteristics of forces acting on a stagnant object is addressed and analyzed.
• Effects of gas velocity on force fluctuation for object in various positions are evaluated.

Large dense objects are easily stagnated over the distributor during fluidization, having serous influence on bed performance. In this study, three-dimensional modeling of the gas–solid flow in a fluidized bed equipped with an inclined air distributor is conducted by means of two-fluid model to explore the characteristics of the force acting on a stagnant object in bottom bed. Images of the instantaneous particle concentration demonstrate the inhomogeneity of transverse gas–solid flow in bottom bed. The influences of gas velocities on the force fluctuation characteristic for object in various positions of the bottom bed are evaluated. Statistical, spectral and wavelet analysis methods are applied to disclose the time-averaged and instantaneous characteristic of the forces. Results show that with the increasing of gas velocity, the transverse movements of bubbles and particles are both intensified, and the latter is more significant. The dominant frequency of the forces on an object along the inclined direction is 0.3–0.5 Hz, which is smaller than that perpendicular to the distributor of 1.2 Hz.

Instantaneous particle concentration distributions with a stagnant object in the bottom bed.Figure optionsDownload as PowerPoint slide