Numerical simulation of gas‐solid heat transfer behaviour in rectangular spouted bed

Abstract

In order to investigate heat transfer behaviour at an individual particle scale, the particle cooling process in a rectangular spouted bed is simulated by the Computational Fluid Dynamics‐Discrete Element Method (CFD‐DEM). As the inlet gas velocity increases, the gas‐particle convective heat transfer in the jet region is intensified, while the convective heat transfer in the annular region is weakened. The inlet gas velocity also has an influence on the particle‐particle conductive heat transfer. Particle‐particle conductive heat transfer in the jet and fountain regions can both be enhanced by increasing inlet gas velocity, but this variation trend is opposite in the annular region. Additionally, the temperature distributions of particle and gas phases in the bed are also analyzed in detail. Compared with the infrared thermography experiment, the particle cooling process in the simulation results agrees closely with that in the experimental results.

Modelling of Spouted and Spout-Fluid Beds: Key for Their Successful Scale Up

“…Yang et al [135] concluded that the influence of the turbulence model in a double slot spouted column was significant in the spout and fountain regions. Wang et al [119] compared gas-solid heat transfer in a spout fluid bed, comparing the effects of including a turbulence model (not specified) or neglecting it; they showed that the inclusion of the model leads to more accurate results, but the difference is negligible, highlighting that the Stokes number of particle is low and thus turbulent diffusion does not affect heat transfer significantly. Saidi et al [120] simulated a spout-fluid bed, neglecting the turbulence effects and obtaining good similarities with experimental data, including pressure drops.…”

“…Wang et al [119] modelled the cooling of particles, initially at 150 • C, when spouted by air flow at ambient temperature. The increase in the rate of the fed gas promoted the convective gas-solid and conductive solid-solid heat transfer in the jet, but hindered them in the annulus region; the temperature of particles was lower in upper sections of the bed, while that of the gas phase behaved oppositely.…”

Experimental Methods in Chemical Engineering: Discrete Element Method—DEM

“…Researchers apply DEM to investigate a large spectrum of unit operations: fluidized and spouted beds; hoppers and silos; mixers; drums; conveyors; furnaces; and spheronizators …”

Effect of Operating Parameters on Gas‐Solid Hydrodynamics and Heat Transfer in a Spouted Bed

“…Additionally, Hosseini et al [17] evaluated the influence of the radial distribution function on the heattransfer behavior of a 2D spouted bed through the Eulerian-Eulerian two-fluid approach. Wang et al [18] investigated the heat-transfer mechanisms in different regions of a spouted bed upon cooling particles. Fattahi et al [8] simulated transient heat transfer in a spouted bed by using the Eulerian-Eulerian method and noted that the simulation parameter of the specularity coefficient played a critical role in particle behavior.…”

“…Wang et al. investigated the heat‐transfer mechanisms in different regions of a spouted bed upon cooling particles. Fattahi et al.…”