Combining EnergyPlus and CFD to predict and optimize the passive ventilation mode of medium-sized gymnasium in subtropical regions

Abstract

Thermal stratification is considered to be common in large space buildings, which constitutes a complex indoor thermal environment of gymnasiums. In consideration of the combined effect of wind pressure and thermal buoyancy on natural ventilation efficiency, this work combining the building energy modeling (BEM) and computational fluid dynamics (CFD) to evaluate the impact of climatic conditions and building forms on natural ventilation of medium-sized gymnasiums in subtropical regions. The ventilation efficiency at peak time (13:00-15:00) is significantly higher than that at valley time (08:00), which indicates that thermal buoyancy plays a positive role in air change rate (ACH) and wind velocity conditions, and the thermal pressure form with low-inlet and high-outlet has a higher climate adaptability. Using the Adaptive Predicted Mean Vote (APMV) to evaluate the comfort of the combining results, and to effectiveness predict the passive ventilation mode in each quarter. There is a large operating time range (71.35% ∼ 100%) for a medium-sized gymnasium in the subtropical regions to apply the passive ventilation mode in transition seasons of spring and autumn, and the thermal comfort condition of the sports area is better than that of the spectator area. On the other hand, the operating time range shows 36.96%–64.93% in summer as the peak time comfort exceeds the upper limit of the standard value. Since the sports crowd has stronger thermal endurance than the sitting crowd, it is possible to achieve a higher range of energy saving by effectively controlling the operation time and power consumption of air conditioning measures in non-event time (no consideration of the use in spectator area) in hot summer.