Study On Natural Ventilation Performance And Structural Optimization Of One-side Wind Catcher

The wind catcher is a special passive natural ventilation equipment.It mainly drives by wind pressure to introduce external wind into the room to achieve enhanced ventilation.In this paper,the method of numerical simulation is used to study the flat,inclined and curved type wind catchers’ ventilation performance.It mainly discusses six factors such as external wind speed(1m/s ~ 6m/s),wind direction(0° ~ 90°),wind catcher’s height,installation position,outlet size and location of outlet,and the influence of these factors on ventilation performance of various types of wind catchers.These types of wind catchers are installed on the top of the office with a building size(length×width× height)of 8m× 6m× 3m.The office has a window on one side and the window area is 1m×m.Pressure coefficient,air volume,uniformity of air supply,average wind speed in indoor working area,average air age and other parameters,comprehensive evaluation of its applicability in the transition season in the northwest region,to provide certain technical guidance for engineering design.The research results show that:(1)Only considering the amount of wind capture,when the external wind speed v≤3m/s,the air intake of the three types of wind catchers is very close,the maximum deviation is 2.1%,and it can be approximated that the average annual wind speed is less than 3m/s area,all three types of wind catchers can be used.When the wind speed v>3m/s,the air intake of the arc-type wind catcher is the largest;(2)When the wind direction angle is greater than 45°,it is not conducive to wind catching by the wind catcher;the uniformity of the air supply of each type of wind catcher increases with the wind speed Larger and lower,it gets better as the wind direction angle increases.Among them,the uniformity of the air supply of the arc-typewind catcher is the best,and the flat type is the worst;(3)In actual engineering,the air volume,air supply uniformity,When indoor air flow and other factors,when the external wind speed v≤3m/s,the inclined or arc-type wind trap is preferred,and the installation angle should be 45° from the local dominant wind direction;when v >3m/ s,the arc surface is selected Type wind catcher and ensure that the installation angle is 0°with the dominant wind direction.Based on the above results,a further study of the flat wind catcher under specific working conditions(v=3m/s,θ = 0°)shows that when the external wind speed is 3m/s and the wind direction angle is 0°,the wind catcher should be Install at a position close to the windward wall,no more than 1/8 of the room depth,avoid installing in the middle of the roof of the building;the wind catcher’s air volume decreases as the height increases,the height is 1.5m When the height is increased to 2.5m,the wind capture volume drops by 33%.The wind catchers of different heights only affect the amount of wind capture and have little effect on the indoor airflow organization;(2)The amount of wind capture varies with the size of the air outlet Increase and increase,when the area of the air outlet is greater than or equal to 1m2,further increase its area,the air intake increases slowly,and the impact on the average wind speed and indoor air quality of the indoor working area is small and can be ignored;(3)The combination of fan and window has good ventilation effect,it is not recommended to install two single-sided wind catchers adjacent to each other(similar to double-sided wind catchers,there is a short circuit phenomenon).