A LATTICE BOLTZMANN-LATTICE GAS AUTOMATA MODEL FOR ANALYSING THE STRUCTURE AND EFFICIENCY OF DEPOSITED PARTICULATE MATTER ON FIBROUS FILTERS

摘要

Fibre filtration, which has the advantage of high collection efficiency of submicron particle, is widely used for air purification at coal-fired power plants, mining engineering, cement industries, work places and life areas. Since the fifties of last century, scientists have been developing mathematical models or carrying out experimental investigations to predict and improve filter performance. However, the filtration process of suspended particles from the airflow is very complicated because of various deposition mechanisms (diffusion, interception, inertial collision, etc) of solid particles as well as the dynamic evolution of filtration efficiency and pressure drop during the filter clogging. In order to construct the optimal fibrous structures with high filtration efficiency (especially for particles of 0.1~1 um), low pressure drop and long lifetime of the filter, it is essential to obtain the detailed information of a non-steady-state filtration process. Numerical simulation of gas-solid two-phase flow provides a promising approach to investigate the deposition of particulate matter on filter fibres.