A corrected filtered drag model considering the effect of the wall boundary in gas-particle fluidized bed

The databases used to construct traditional mesoscale drag models is usually obtained from fine-grid simulation results in the full-periodic domains, ignoring the function of the wall boundary. In actual fluidized bed reactors, the presence of wall boundary can significantly affect the heterogeneous structures in near-wall areas, thereby affecting the drag force. Therefore, this work aims to further enhance the performance of the prediction results of existing filtered drag model by introducing the influence of the wall boundary. Based on the mesoscale drag force model published in previous literature, a correction coefficient considering the influence of the distance from the grid to the wall boundary is proposed. The applicability of the new corrected model is further enhanced by introducing the influence of solid volume fractions and slip velocities. Simple posteriori validations are systematically conducted in various common fluidized beds including the bubbling bed, the turbulent bed, and the fast bed to assess the predictive capability of the newly proposed correction drag model.