About Measuring the Anemometer
Practice has proven that the 16mm probe of an anemometer is the most widely used for measuring airflow velocity in pipelines.
Its size ensures good permeability and can withstand flow velocities up to 60m/s. The measurement of airflow velocity inside pipelines is one of the feasible measurement methods, and the indirect measurement protocol (grid measurement method) is applicable to air measurement.
2. The measurement vent in the exhaust system will greatly alter the relatively balanced distribution of airflow in the pipeline: a high-speed zone is generated on the surface of the free vent, 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, measurements are usually taken using a large-diameter rotor with a high anemometer. Because a larger diameter can average uneven flow velocity and calculate its average value over a larger range.
3. In the measurement of the exhaust hole, even if there is no interference from the grid at the exhaust point, the air flow path has no direction, and its airflow 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)
