.png){kind=icon}
.png){kind=icon}
Return
A sub-grid gas-solid interaction model for coarse-grained CFD-DEM simulations
.png){kind=icon}
PRE
AI
DOI：10.1016/j.cej.2024.155042.png)
.png){kind=icon}
Original request for help.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
Computational fluid dynamics has been coupled with coarse-grained discrete element method (CFD-CGDEM) to study industrial-scale gas-solid fluidized beds. However, solving the fluid flow at a grid size of several coarsegrained particles (CGPs) cannot accurately predict the gas-solid interaction, and thus reasonable correction model is required. This study develops a sub-grid model to correct the gas-solid interaction and thereby improve the accuracy of coarse-grid CFD-CGDEM simulation. First, the fluid grids with the size of several CGPs are divided into the auxiliary three-dimensional sub-grids. Then, the CGPs are mapped onto the sub-grids by the weight function to reconstruct the local solid velocities and solid fractions of the sub-grids. After that, the simplified mass and momentum conservation equations are solved to resolve the local gas velocities of sub-grids. Finally, the drag on each CGP is corrected based on the local gas-phase hydrodynamics of sub-grids. Results show that the sub-grid model resolving the local gas velocity in all the three directions works better than that just in the main stream direction. The coarse-grid CFD-CGDEM simulations with this sub-grid model agree well with the experiment for the bubbling, turbulent and rapid fluidized beds. Besides, by solving the simplified conservation equations with graphics processing units, the coarse-grid CFD-CGDEM coupled with the sub-grid model achieves 674 times speedup compared to the fine-grid simulation, demonstrating a much more efficient method to study industrial-scale gas-solid fluidized beds.
Keywords:
Sub-grid
Coarse-grain
CFD-DEM
Gas-solid flow
Journal
IF:
13.2
Papers:
7.4W
Citations:
48.5W