Investigation and low energy improvement of the thermal environment of work areas in the Qingdao Metro in winter

Few studies have investigated the thermal environment of the work area hall in underground metro stations during winter. Two underground stations were chosen within Qingdao Metro Lines 2 and 3 to investigate the thermal environment in the work area hall in northern city metros in China. Air temperatures and wind velocity parameters were identified as key influencing factors and were continuously measured in the work area. The study found that the thermal environment fluctuates frequently in the work area throughout the day. Changes in temperatures and wind speeds were periodically caused by piston wind flowing from the platform level. To improve this heating situation in the work area in winter, the study proposes recycling waste heat from the power equipment rooms, using the air source but through the water cycle heat pump system. Insights from the study may help save energy and improve the thermal environment, and could be applied across metro stations in north China cities in winter.

Practical application: The thermal comfort of the working area in the metro station hall is extremely poor as indicated by a study of Qingdao Metro stations. This paper explores the application of a heat pump as a means of heating the working area to improve the cold and damp winter environment for the metro staff using waste heat from the machine rooms.