Anemometer: An Ideal Way to Calculate Velocity of the Wind

The anemometer was discovered by John Thomas Romnay Robertson to measure the velocity of wind pressure. They are of many types. Generally, an anemometer consists of four arms with hemispherical shaped cups that are at right angles to each other and it is connected to a shaft vertically. When the wind blows the cups rotates and the number of turns within a certain period of time will give the speed of the wind. The different types of anemometers are:

Cup Type Anemometers

They consist of four hemispherical cups that have attached arms. The cups are of equal size connected with a rotating wheel on a pole. It measures the speed of the wind indicating the direction. The accuracy of the speed of the wind can be found by using three cups on arms which are varying in length. To improve the accuracy, grooves were made on the cups. There are still researches going on to improve the accuracy on new designs. They are mainly used to find out the velocity of wind and modern versions mostly implemented at airfields and on ships.
Propeller Anemometers
They are also called windmill or spinners that are used to measure the speed of the wind, which is calculated by the speed of the spinning. There is another type, the rear or reverse prop, which has blades on the rear that faces the wind. It is a device mounted on a wheel and it can calculate the velocity in both directions.
The technology has developed this device to have electronic sensors, which can be monitored by the computers to calculate accurate directions in respect to degree, range and velocity of wind. They are mainly used in farm-based landing plots and small airports for guidance for takeoffs and landings. Unlike the cup type they are mounted horizontally.
Doppler
They are laser type devices which have a beam of light to calculate the speed of the wind. The air molecules float in the region of the beam where the light is reflected to the device. The velocity is calculated based on the original light beam.
Hot Wire Anemometers
They are mostly used for measuring high frequency responses. In this type, a fine wire is heated to a certain temperature. The air which flows across the hot wire will cool down the wire and the cooling process can be recorded to calculate the flow velocity. There are also sonic and tube anemometers available that measure wind direction and speed. They are also used in ships for navigation, and on bridges

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Chris enjoys writing articles on topics like anemometer and what causes wind. Visit to read more detail.