◆Wind cup anemometer
It is the most common type of anemometer. The rotating cup anemometer was first invented by British Robinson, and it was four cups at that time, and then it was changed to three cups. Three parabolic or hemispherical empty cups fixed on the rack at 120 degrees to each other are all on one side, and the entire rack together with the wind cup is mounted on a freely rotatable shaft. Under the action of the wind, the wind cup rotates around the axis, and its rotational speed is proportional to the wind speed. The rotational speed can be recorded by electric contact tachogenerator or photoelectric counter.
◆Propeller anemometer
It is an anemometer with a set of three- or four-bladed propellers rotating around a horizontal axis. The propeller is installed at the front of a wind vane, so that its rotation plane is always facing the direction of the wind, and its speed is proportional to the wind speed.
◆Hot wire anemometer
A wire heated by an electric current, the flowing air dissipates heat, and the heat dissipation rate and the square root of the wind speed are linearly related, and then linearized by the electronic circuit (for easy scale and reading), the hot wire anemometer can be made. There are two types of hot-wire anemometers: side-heating and direct-heating. The side-heated hot wire is generally a manganese copper wire with a temperature coefficient of resistance close to zero, and a temperature measuring element is placed on its surface. Most of the direct-heating hot wires are platinum wires, which can directly measure the temperature of the hot wire itself while measuring the wind speed. The hot-wire anemometer has high sensitivity at low wind speed and is suitable for measuring small wind speed. Its time constant is only a few hundredths of a second, and it is an important tool for atmospheric turbulence and agrometeorological measurements.
◆Digital
The digital anemometer is a large-scale intelligent wind speed sensing and alarm device specially developed for various large-scale mechanical equipment. The microprocessor of the advanced digital anemometer is used as the control core inside, and the peripheral adopts advanced digital communication technology. The system has high stability, strong anti-interference ability, and high detection accuracy. The wind cup is made of special materials, with high mechanical strength and strong wind resistance. The design of the display case is novel and unique, sturdy and durable, and easy to install and use. All electrical interfaces are in line with international standards, no debugging is required during installation, and they are suitable for different working environments. The digital anemometer is used to measure the instantaneous wind speed and average wind speed, and has functions such as automatic monitoring, real-time display, and over-limit alarm control.
◆Acoustic Anemometer
The wind speed component in the direction of sound wave propagation will increase (or decrease) the sound wave propagation speed, and the acoustic anemometer made with this characteristic can be used to measure the wind speed component. The anemometer has at least two pairs of sensing elements, each pair includes a sounder and a receiver. Make the sound waves of the two sounders travel in opposite directions. If one group of sound waves propagates along the wind speed component and the other group just travels against the wind, the time difference between the two receivers receiving the sound pulse will be proportional to the wind speed component. If two pairs of components are installed in the horizontal and vertical directions at the same time, the horizontal wind speed, wind direction and vertical wind speed can be calculated respectively. Due to the advantages of anti-interference and good directivity of ultrasonic waves, the frequency of the sound waves emitted by the acoustic anemometer is mostly in the ultrasonic section.
