TO THE PROBLEM OF DETERMINING AIR VELOCITY FIELD IN TUNNEL STRUCTURES OF A SUBWAY LINE USING CIRCULAR MODELS AS A METHOD OF TOPOLOGICAL DECOMPOSITION

Abstract

Underground subway structures represent crowded public areas; therefore, they are subject to high requirements for maintaining the standard microclimate parameters at stations and in tunnels, including the content of suspended dust in the air. To maintain dust concentration within specifications, it is proposed to use air filters installed in station ventilation connections in the stream of air from the piston effect of trains. To study the piston effect by aerogasdynamic computational methods, a method is proposed for the topological decomposition of a subway line - transition froma complete linear model to a closed circular model by isolating several lines and closing them into a circle, which allows reducing the size of discrete model of the design section, while maintaining the influence of neighboring lines and stations as well as calculation accuracy. As a result of a numerical experiment, the parameters of transient air distribution from the piston effect of trains and the structure of air stream at the places of filter installation are determined for further study of their geometric, structural and operational parameters.