通风管道内风速及风量的测定事项

发布人：   发布时间：2023-06-05 17:17:02

(一)测定位置的选择

（1） Selection of measurement position

澳门正版内部资料大公开通风管道内风速及风量的测定，是通过测量压力换算得到。测得管道中气体的真实压力值，除了正确使用测压仪器外，合理选择测量断面、减少气流扰动对测量结果的影响很大。测量断面应尽量选择在气流平稳的直管段上。

The measurement of wind speed and air volume in Jinan ventilation ducts is obtained through pressure conversion. To measure the true pressure value of gas in the pipeline, in addition to using pressure measuring instruments correctly, selecting a reasonable measurement section and reducing airflow disturbance have a significant impact on the measurement results. The measurement section should be selected as much as possible on a straight pipe section with smooth airflow.

测量断面设在弯头、三通等异形部件前面(相对气流流动方向)时，距这些部件的距离应大于2倍管道直径。当测量断面设在上述部件后面时，距这些部件的距离应大于4～5倍管道直径。

When the measuring section is set in front of irregular components such as elbows and tees (relative to the direction of airflow flow), the distance from these components should be greater than twice the pipe diameter. When the measuring section is set behind the above-mentioned components, the distance from these components should be greater than 4-5 times the pipe diameter.

当测试现场难于满足要求时，为减少误差可适当增加测点。但是，测量断面位置距异形部件的小距离少是管道直径的1.5倍。

When it is difficult to meet the requirements on the testing site, measurement points can be appropriately increased to reduce errors. However, the small distance between the measurement section position and the irregular component is at least 1.5 times the diameter of the pipeline.

测定动压时如发现任何一个测点出现零值或负值，表明气流不稳定，该断面不宜作为测定断面。如果气流方向偏出风管线15°以上，该断面也不宜作测量断面

If a zero or negative value is found at any measuring point during the measurement of dynamic pressure, it indicates that the airflow is unstable, and this section should not be used as the measurement section. If the airflow direction deviates more than 15 ° from the centerline of the air duct, this section should not be used as a measurement section

(检查方法：毕托管端部正对气流方向，慢慢摆动毕托管，使动压值大，这时毕托管与风管外壁垂线的夹角即为气流方向与风管线的偏离角)。

(Inspection method: The end of the pitot tube is facing the airflow direction, and slowly swing the pitot tube to increase the dynamic pressure value. At this time, the angle between the pitot tube and the vertical line of the outer wall of the air duct is the deviation angle between the airflow direction and the centerline of the air duct.).

选择测量断面，还应考虑测定操作的方便和。

When selecting a measurement section, consideration should also be given to the convenience and safety of the measurement operation.

(二)测试孔和测定点

（2） Test holes and measuring points

由于速度分布的不均匀性，压力分布也是不均匀的。因此，必须在同一断面上多点测量，然后求出该断面的平均值。

Due to the non-uniformity of velocity distribution, the pressure distribution is also non-uniform. Therefore, it is necessary to measure multiple points on the same cross-section and then calculate the average value of that cross-section.

圆形风道

Circular duct

在同一断面设置两个彼此垂直的测孔，并将管道断面分成一定数量的等面积同心环，对于圆形风道，测点越多，测量精度越高。

Set two perpendicular measuring holes on the same section and divide the pipeline section into a certain number of equal area concentric rings. For circular air ducts, the more measuring points, the higher the measurement accuracy.

矩形风道

Rectangular duct

可将风道断面划分为若干等面积的小矩形，测点布置在每个小矩形的，小矩形每边的长度为200mm左右，圆风管测点与管壁距离系数(以管径为基数)。

The cross-section of the air duct can be divided into several small rectangles of equal area, with measuring points arranged at the center of each small rectangle. The length of each side of the small rectangle is about 200mm, and the distance coefficient between the measuring points of the circular air duct and the pipe wall (based on the pipe diameter).

通风管道内风速及风量的测定事项就讲解到这里了，希望能够给您好的帮助，更多事项就来我们网站咨询！

That's all for the measurement of wind speed and airflow inside the ventilation duct. We hope it can be of great help to you. For more information, please come to our website consulting service