The relationship between the site selection of a hilly terrain and the natural ventilation of the Dangdamen building complex,which is a traditional folk house,is revealed by a computational fluid dynamics（CFD）simulation.The wind press and speed distributions around the building in four cases with different weather conditions and topographies are simulated.The simulation results show that a hill can reduce the absolute values of the wind pressure at the windward and leeward sides of the building.The encouraging effect of the patio on the natural ventilation in a terrain with a hill is greater than that without a hill.The same situation occurs when comparing the patio effects between summer and winter.The wind speed around the building can be reduced by the hill as it is an obstacle and the degrees of the influence of the hill in summer and in winter are quite different because of different wind directions.The analysis results show that this kind of site selection,with the hill to the north,is a suitable way to settle the conflict of the natural ventilation requirements in summer and in winter under subtropical climate conditions,especially in houses with patios.
A case study is performed on the influence of the patio on the indoor environment of a traditional folk house group,named Zhangguying village in Hunan province,in the summer of 2007.Measurements include indoor and outdoor air temperature,indoor and outdoor illuminance,indoor and outdoor air speed,and carried out from August 5th to 10th.The results show that the patio,acting as a ＂buffer zone＂,can reduce the ambient impacts on the indoor thermal environment of rooms because the temperature of the patio is lower than that of the outdoor temperature but higher than that of the rooms.The patio can improve the indoor lighting environment because the illuminance of the patio is lower than that of outdoor and higher than that of the rooms.But the effect is too limited,because the illuminance of the rooms is lower than the national standards.This study shows that the shading design is the primary consideration in this kind of climate.The wind speed of the patio is stable and similar to that of the hall and the stack effect of the patio is not obvious.It shows that the patio is useful for natural ventilation,caused by wind pressure,in summer.
