Anemometer Measurements in Air Intake and Exhaust Systems
The ventilation port will greatly change the relatively balanced distribution of airflow inside the pipeline: a high-speed zone is generated on the surface of the free ventilation port, while the rest of the area is a low-speed zone, and vortices are generated on the grid. According to different design methods of the grid, the airflow cross-section is relatively stable at a certain distance (about 20cm) in front of the grid. In this case, the measurement is usually carried out using a large anemometer/anemometer caliber wheel. Because a larger diameter can average uneven flow velocity and calculate its average value over a larger range.
Anemometer/anemometer uses a volumetric flow funnel for measurement at the suction port:
Even without the interference of grids at the exhaust point, the airflow path has no direction and its cross-section is extremely uneven. The reason is the local vacuum inside the pipeline, which extracts air in a funnel-shaped manner into the chamber. Even in areas very close to the extraction, there is no position that meets the measurement conditions for measurement operations. If the grid measurement method with average calculation function is used for measurement, and the volumetric flow rate method is used for measurement, only the pipeline or funnel measurement method can provide reproducible measurement results. In this case, measuring funnels of different sizes can meet the usage requirements. By using a measuring funnel, a fixed section that meets the flow velocity measurement conditions can be generated at a certain distance in front of the sheet valve. The center of the section can be measured and fixed, the center of the section can be measured and fixed, and the center of the section can be measured and fixed. The measured value obtained by the flow velocity probe is multiplied by the funnel coefficient to calculate the extracted volumetric flow rate. (such as funnel coefficient of 20)
