Study on hybrid ventilation effect of small and medium-sized railway station buildings in different climate regions of China

Abstract

The hybrid ventilation system, which comprises natural ventilation, mechanical ventilation and air conditioning system, offers significant benefits in terms of indoor thermal comfort and energy saving in railway station buildings. This paper takes typical small and medium-sized railway station buildings as an example, and proposes a hybrid ventilation system control strategy with ventilation switching temperature and enthalpy as control parameters, the effects of hybrid ventilation across five climate regions in China are analyzed by building simulation method. The optimal temperature ranges for switching between natural ventilation and mechanical ventilation, determined by thermal comfort and energy efficiency, are 14 ° C to 16 ° C and 22 ° C to 23 ° C, respectively. Meanwhile, the non-air-conditioning thermal comfort hours and energy saving amount both increases gradually from severe cold region, cold region, hot summer and cold winter region, hot summer and warm winter region to moderate region, with the longest thermal comfort hours of 4736 hours and the highest energy saving potential of 20.6 KWh/m2·a in moderate region. However, due to the difference of climatic factors and ventilation operation time in each region, the percentage of non-air-conditioning thermal comfort hours and energy saving rate both decreases gradually from moderate region, severe cold region, cold region, hot summer and cold winter region to hot summer and warm winter region, with the lowest percentage of non-air-conditioning thermal comfort hours of 55.1% and the lowest energy saving rate of 11.5 % in hot summer and warm winter region. The application of hybrid ventilation in railway station buildings yields excellent results in China.