Study On The Potential Of Wind Pressure Natural Ventilation In Residential Buildings

Natural ventilation is one of the main ventilation methods in cities and buildings,which is mainly divided into thermal pressure ventilation and wind pressure ventilation.Due to the small storey height,residential buildings mainly use wind pressure ventilation.However,as the urban population becomes more and more dense,the density of residential buildings is increasing,the atmospheric horizontal wind speed is greatly weakened,and the wind pressure and ventilation potential are significantly lowered.Therefore,this article will conduct in-depth research on the influencing factors and laws of the wind pressure and ventilation potential of residential buildings,and explore the methods and technologies to increase the ventilation rate.This paper first uses wind tunnel experimental data and CFD simulation results to make a rigorous comparison to verify the reliability of CFD simulation.The specific content is divided into three parts: First,by proposing a wind pressure and ventilation estimation model,it explores the different nature of a single building.The ventilation potential of the climate zone.Second,by proposing a new type of building structure of horizontal airflow ventilation,the effect of horizontal airflow channels on the draught of a three-family apartment with one staircase is studied.Thirdly,by adopting different layout forms for the building complex,to explore its influence on the ventilation potential of each building.Research on the ventilation potential of a single building shows that wind speed is positively correlated with wind pressure ventilation rate;In some cities,the ventilation time is longer,but the natural ventilation is relatively low.For example,cities such as Guangzhou and Nanning,which were previously considered suitable for natural ventilation,have low wind speeds and relatively small ventilation,which may reduce the cooling capacity of natural ventilation and increase the possibility of users turning on air conditioners.A study on the ventilation potential of a three-family apartment with one ladder shows that when a resident is on the leeward side,the wind pressure ventilation effect is not good.When the horizontal air flow channel is set,the ventilation volume of seven cities in five typical climate zones in China is predicted through De ST software.The display: the horizontal air flow channel can significantly increase the ventilation volume of the rear wind apartment,the window-to-ground ratio increases by 1%,and the ventilation volume increases.Approximately 6%;Especially for rooms where the airflow channels are directly connected,the ventilation volume has been significantly increased.This paper further proposes that the two evaluation indicators of "wind pressure coefficient difference average" and "wind pressure coefficient standard deviation" are similar,and both can be used to evaluate the wind pressure and ventilation potential of each building in an area.Studies have shown that: when the buildings are aligned,when the wind direction blows from parallel to the arrangement direction,the denser the building,the smaller the ventilation potential,and the more uneven the distribution of the ventilation potential;When the buildings are arranged in a staggered arrangement,when the wind direction blows from parallel to the arrangement direction At the same time,the ventilation potential is more evenly distributed than the positive arrangement;the overhead can increase the ventilation potential of the buildings in the middle of the area.What is different from the past is that the ventilation potential difference between the positive arrangement and the staggered arrangement is very small when the wind direction enters the whole year.This is because it is positive arranged in most wind downwards,and the ventilation effect is still good.This is different from general understanding.The research methods and conclusions of this article can provide references for the initial planning and design of residential buildings.