The effect of a building on the wind speed around it

The dense existence of high-rise buildings in Shanshi has changed the regional environment and has had a negative impact on the factory from another aspect. When the wind hits the high-rise building, it passes through the left and right sides of it, and the wind passing through the surface and the left and right sides of the wind passes, and the contraction of the air flow is negative to the factory. A vortex ensues.

If there are other buildings in the vortex area, they will be affected by the wind environment. When the wind encounters the block of the high-rise building, in addition to most of the direction and both sides of the passage, there is also a part of the downward to the ground, Ran forcibly separates to the left and right sides of the building, this kind of high-rise building around the ground air flow in addition to affecting the nearby low-rise buildings, will also make the building in and out of the factory in the factory strong airflow. Empty r:. between buildings

1', the wind speed increases, the whirlwind appears at the corner, and the higher the building, the more obvious this phenomenon is. Super high-rise buildings.

Even in relatively quiet climates, they can surround themselves with violent air flows, vortices, air currents and gusts of wind.

The denser the cluster of high-rise buildings, the more dramatic this situation will be.

The impact of these changes in wind environment on the environment can be divided into three aspects: Impact on the pedestrian floor. When the strong wind of the mountain hits the high-rise building, part of the wind blows down from a high place to the pedestrian area, and the factory is very uncomfortable.

impact on the use of the building itself. The wind in different directions of the mountain is l+: makes it difficult to open the door of the high-rise building, and the wind in the opposite direction is l+:

Affecting the intake and discharge of air conditioning and ventilation, the windows must be equipped with safety devices; The window frame should be weatherproof and sealed to make people in high-rise buildings feel uncomfortable. Impact on the surrounding environment: Splashes from nearby fountains, destroying plants and trees.

The vortex of the wind strikes pedestrians, vehicles, etc. on nearby roads.

Influential. Especially high-rise buildings, high-rise buildings can change the direction of wind flow and even change the local microclimate!

A narrow tube effect is formed, which increases the wind speed.

The provisions of the "Dutch Regulations" explain that in the atmospheric boundary layer, the wind speed increases with the height above the ground. When the pressure field does not change with the height, the law of wind speed increasing with height mainly depends on the ground roughness and the vertical gradient of temperature.

It is generally believed that at an altitude of 300 500 m above the ground, the wind speed is no longer affected by the roughness of the ground, that is, the so-called "gradient wind speed" is reached, which is called the gradient wind height. Areas with low ground roughness levels have lower gradient wind heights than areas with higher ground roughness ratings.

This is just a summary judgment of statistical data for the architectural profession, and it is usually believed that when the height above the ground is 300 500m, the wind speed is no longer affected by the ground roughness, which is enough as a design basis. If you have to know why it stabilizes after more than 450m, you may need to study aerodynamics.

This is based on the data in the table of "Code for Loads on Building Structures".