The Influence Of Openings Of High-rise Residential Buildings And Openings Among Buildings On Wind Environment

With the development of urbanization, because of the demand for human life and building functions, a large number of high-rise residential buildings set up rest platforms, corridors, propylaea, sightseeing corridors, overhead connectors, fire corridors, channels and all forms of building openings and openings among buildings. The appearance of building openings and openings among buildings will change the wind field around the buildings and have a large influence on the wind environment around the buildings. In this paper,the influence of building openings and openings among high-rise residential buildings on wind environment has been in-depth analysis by using numerical simulation method. The study results show that:(1) The area of the wind shadow is reduced after the holes at the bottom of buildings are opened; flow acceleration is formed in the channel of the openings and the flow rate is significantly increased in comparison with the incoming flow. With the increase in the opening width, the average value of the wind speed ratio of each position in the openings sees a drop after an increase. When the opening is narrow, the "hysteresis phenomenon" of hole wall on wind is obvious;when the opening is wide, the wind in the opening increases with the increase in the opening width; the wind speed decreases and the wind flow is more uniform.(2) Under the same opening width, the increase in the opening height has little effect on the wind speed of pedestrian height areas. When the opening height is no more than twice the opening width,there is not an obvious distinction of the wind speed between the top and the bottom of the building openings and the air pressure difference distribution of the building surface is similar to the situation when the holes are not opened;when the opening height of buildings further increases, the wind speed on the upside is significantly higher than it at the bottom. The highest wind speed location is near the outlet on the upside of the hole.With the opening height increasing,the maximum value of the wind speed in the opening become higher; the eddy current around buildings reduces; the area of the wind shadow reduces and air pressure difference value of the building surface becomes smaller.(3) With the increase in the angle between the opening surface of buildings and the incoming flow direction, namely the frontal area of the hole increases,the average value of the wind speed ratio at pedestrian height areas increases before decreases and the wind speed in the entrance channel is more smooth and uniform.When the angle is 67.5°, the average value of the wind speed ratio is maximum, at 1.71; when it continues to increase to 90°, the average value of the wind speed ratio reduces by 34%. When the angle is a little smaller, the wind speed in the opening channel varies a lot and the airflow is not uniform.(4) With the widening of openings between buildings,the wind speed in the hole decreases; the effect on each other between both sides of the buildings weakens if the highest wind speed location is farther away from the openings on the windward side. The air flow in the channel of the openings between the buildings is formed by one side based around wind before changes into wind around on both sides, then further changes into the complex flow which is composed by wind around on both sides and the wind draught of the incoming flow.(5) Based on the above findings, the design strategy of the hole width,height, direction of high-rise residential buildings and the openings among high-rise residential buildings is proposed, which can be used to guide the opening design of high-rise residential buildings and optimize the architecture design, improving the outdoor wind environment.