Cfd Analysis of Air Flow Organization in the Public Area of Island Platform Subway Station

Abstract

This paper conducts a CFD analysis on the airflow field in the public area of an island-platform subway station. By considering the operational conditions and working modes of the air-conditioning and ventilation system in the public area of the subway station, boundary conditions are determined for the four seasons: spring, summer, autumn, and winter. The velocity field distribution under typical operating conditions for each season in the public area of the subway station is then obtained. Based on the comparison and analysis of the calculation results according to the relevant standards for environmental indicators in subway stations, it was found that the wind speed in the public area of the subway station was excessively high during summer conditions, resulting in a waste of energy from the air-conditioning units. To improve the air distribution characteristics within the station and reduce the degree of airflow unevenness, a suggestion was proposed to alter the proportion of air supplied through the air ducts. After the improvement, the airflow velocity distribution in the public area of the station became more uniform. The airflow velocity in the station hall was 0.30 m/s, which was an 11.8% decrease compared to before the improvement. The airflow velocity in the platform layer was 0.35 m/s, representing a 10.3% reduction from the pre-improvement level. The airflow velocity in the public area basically met the relevant standards and regulations. This study theoretically reveals the air flow law in the public areas of subway stations, and provides scientific reference for the energy-saving improvement measures of subway ventilation systems.

Keywords: Island Platform Subway Station, Air Flow Organization, CFD, Energy conservation