Numerical Modeling of Dust-and-Air Flow in Air Filtering System in Subway Tunnel Ventilation

A promising approach to air dedusting in tunnel ventilation in subways is inertia filters which have low air drag and can efficiently catch coarse and medium-size dust particles without addition of sophisticated equipment as dust-laden air flow through the filters is assisted by piston effect in train tunnels. An approach to the numerical modeling of a multi-phase flow in an inertia filter is substantiated. The validation of the approach is proved by the qualitative and quantitative coincidence of the numerical modeling results and lab-scale inertia filter test data. The numerical research findings helped determine the influence exerted by air velocity, dust size and filter surface characteristics on the dust catching efficiency. The design of the filter to be installed at an air connection in a single-track subway tunnel is developed.