Research on thermal pressure ventilation air volume of a subway station

Taking a subway station in Shanghai as the experimental object, this paper conducts theoretical calculations based on the principle of station air thermal balance, obtains the thermal pressure ventilation air volume, and studies the relevant characteristics. The research results show that the thermal pressure ventilation of the subway station is significantly affected by the temperature difference between outdoor and indoor temperatures. In winter (January, February and December), the thermal pressure ventilation air volume in each month accounts for 56.5%, 45.3%, and 50.1% of the total ventilation volume at the inlet and outlet, respectively. The average air volume of thermal pressure ventilation in each month is 29 849 m3/h, 24 024 m3/h, and 25 425 m3/h, respectively, accounting for approximately 83%, 67%, and 71% of the capacity of the outdoor air handling unit in the standard station. The thermal pressure ventilation takes away a large amount of heat, causing the air temperature inside the station to be generally below 18 ℃. During transition season (March, April, October and November), the thermal pressure ventilation air volume in each month accounts for 40.9%, 40.8%, 42.7%, and 55.3% of the total ventilation volume at the inlet and outlet, respectively. The average air volume of thermal pressure ventilation in each month is 20 499 m3/h, 23 628 m3/h, 23 643 m3/h, and 24 131 m3/h, respectively, accounting for approximately 57%, 66%, 66%, and 68% of the capacity of the outdoor air handling unit of the standard station. The air temperature inside the station is mainly from 20 ℃ to 28 ℃, which can meet the thermal comfort requirement of passengers without turning on mechanical ventilation system every day. Therefore, the energy consumption of the mechanical ventilation can be decreased.