DEM-CFD modeling and simulations of hydrodynamic characteristics and flow resistance coefficient in fixed-bed reactors

Abstract

Fixed-bed reactors are widely used in chemical process industries. Many flow resistance coefficient correlations have been proposed for optimal design. However, these correlations usually have their own character and application scope. Therefore, the in-depth comparison and verification analysis of these drag coefficient correlations are conducive to their correct use. In this study, the discrete element method was employed to develop fixed-bed reactors with different tube-to-particle diameter ratios. Then a large set of computational fluid dynamics (CFD) simulations were conducted to investigate the hydrodynamic characteristics with respect to different inlet velocities and particle sizes, and the simulated pressure drop data were used to calculate the flow resistance coefficient. The output flow resistance coefficients were compared with those calculated by the classical models in laminar and turbulent flow regimes. It was found that the developed DEM-CFD approach was effective to evaluate the scope of applicability of the reported flow resistance coefficient correlations.

Keywords

• Fixed-bed reactors
• Discrete element method
• Computational fluid dynamics
• Pressure drop
• Flow resistance coefficient