How to choose the wind volume hood and anemometer
The price difference between the air volume hood and the anemometer is very large, and customers often have such questions: Can the anemometer replace the air volume hood?
The air volume hood is mainly composed of three parts: the air volume hood, the base, and the PDA. How to choose the air volume hood and the anemometer
The air volume cover is mainly used to collect the air volume and gather the wind to the wind speed homogenizer on the base. A wind pressure sensor is installed on the wind speed uniformity, and the sensor can reflect the change of the wind speed. The wind volume meter adopts the pitot tube principle to automatically detect the wind pressure at multiple points and multiple time points, and then calculate the air volume according to the size of the base to generate the average air volume (m3/h). The display of the air volume hood adopts PDA, and the large-screen LCD display is intuitive, and the data of wind speed, temperature and air volume can be obtained directly, and the recording time interval can be set for continuous parameter recording, so as to analyze the data. The measured and recorded data are recorded on the memory card and will not be lost. The data can be transferred to the PC through the serial port of the computer for further application.
The use of anemometer: the flow velocity measurement range from 0 to 100m/s can be divided into three sections: low speed: 0 to 5m/s; medium speed: 5 to 40m/s; high speed: 40 to 100m/s. The thermal probe of the anemometer is used for the measurement of 0 to 5m/s; the wheel probe of the anemometer is ideal for measuring the flow velocity of 5 to 40m/s; and the best results can be obtained in the high speed range by using the pitot tube. An additional criterion for the correct selection of an anemometer's velocity probe is temperature, usually the thermal sensor of an anemometer is used at a temperature of about +-7˚C. The rotor probe of the special anemometer can reach 35˚C. Pitot tubes are used above +35˚C.
Anemometers generally measure at a single point, and the accuracy of the test data is not high. When the tuyere produces vortex/jet flow, the wind speed is not very accurate, and one tuyere needs to measure several points, or even a dozen points to get the average wind speed. If there are several high-efficiency air supply outlets, it will be very troublesome. It takes a lot of time to test and calculate according to the area of the tuyere, and the accuracy is not enough. Therefore, the air volume hood is the most suitable choice for strict dust-free places.
