Numerical comparison of fluid dynamics in bag filters using different porous media models
WU Jingdong
YANG Xuelian
WANG Yunpeng
ZHANG Jiawei
ZOU Yang
LI Mengke
ZHU Mengqi
Abstract：Accurate characterization of the filter material as a porous medium is critical for computational fluid dynamics(CFD)simulations of bag filters.This study systematically evaluates two prevalent models—the porous jump model and the porous continuous model—to assess their applicability.The results show that both models predict a similar four-stage development of the internal transient flow(injection-entrainment,impact development,turbulent diffusion,and steady-state establishment)and agree on the overall trend of axial velocity along the filter bag.However,the porous continuous model demonstrates superior performance.By explicitly representing the porous layer thickness and incorporating the coupled effects of viscous and inertial resistance,it more accurately captures the flow rectification by the porous layer,the evolution of large-scale vortex structures,and the permeation of ambient fluid into the porous medium.Moreover,simulations using the porous continuous model reveal a pronounced longitudinal pressure gradient inside the filter bag,a feature not adequately captured by the jump model.Consequently,the porous continuous model provides a more realistic representation of the fluid-porous media interactions under practical conditions,yielding higher simulation accuracy and greater value for engineering applications.
Keywords：bag filterporous media modelcomputational fluid dynamics(CFD)airflow distributionnu-merical simulation
Publication Date：2025-11-20
Online Publishing Date：2026-01-06(First online date of this platform, not the publication date of the document)
Pages：10( 33-42 )