Steady-state CFD simulation of gas-solid flow for inlet boundary conditions in a fluidized bed

Abstract

Multiphase fluidized bed is extensively used in various industries because of its characteristics of high heat transfer rate, low pressure drop, uniform temperature distribution, and large contact area which enhance chemical reaction. In this study, two dimensional modelling of different inlet configurations for fluidized bed is developed to study the solid volume fraction and axial velocity profiles as well as gas solid mixing patterns at the different inlet configurations. Based on Eulerian–Eulerian multiphase and k-ɛ turbulence model, the interactions between phases have been simulated using ANSYS FLUENT. Three different inlet configurations and two type of boundary conditions with “no slip” and “partial slip” wall are investigated. Sensitivity studies of the model involving three parameters are also compared to identify the sensitivity behaviour among these parameters. The key finding of this study is to identify the best inlet configuration on fluidized bed design. Results show that the inlet configuration for FB-B is observed to have the closest agreement with the previous study. Sensitivity studies among three parameters Specularity Coefficient (φ), Particle–particle RestitutionCoefficient (es) and Particle–wall RestitutionCoefficient (ew) are also investigated and results show no sensitivity effect for φ and ew. However, results show es factor has a sensitivity effect in correctly predicting the core-annulus flow in the fully developed region of fluidized bed.