Anemometer And its Types

An anemometer is a handheld instrument which is primarily used to measure wind speed and wind gusts. A hand held anemometer is a unit that measures wind pressure but due to the nature of speed and pressure the anemometer although designed for the purpose of measuring velocity will also measure pressure. The anemometer was originally developed by Leon Battista Alberti back in 1450 but has been modified and streamlined over hundreds of years and is now available as a digital hand held anemometer that is readily available today

The anemometer was originally designed for use at weather stations but is now used in many industries or for other activities such as farming and even golf. Whatever industry or sport is played outdoors can utilize an anemometer effectively to gauge wind effects.

The name ‘anemometer’ was originally derived from the Greek word anemos which means wind and is used in any aspect of meteorology or aerodynamics. It was generally only used to determine wind speed but in 1991 it was further developed to measure wind direction too.

There are a number of types and designs of anemometers

·         The cup anemometer – a relatively simple design of four mounted cups which would measure the wind flow this design is still used extensively as a standard measure for wind resource assessment.

·         Vane anemometers – which work on the same basis as a windmill and measures wind speed and flow rate and is generally used where wind flow is consistently in the same direction as in a closed environment such as a mine shaft.

·         Hot wire anemometers – use fine wires which are heated and measures are obtained by the resistance of wind flow on the heated wires. This is described as a thermal measurement.

·         The Laser Doppler Velocimetry – which measure velocity using a beam of light.

·         Ultrasonic anemometers - which use ultrasound waves to measure the wind speed and are generally used to detect turbulence.

·         Acoustic resonance anemometers – are a variation of ultrasonic anemometers using acoustic waves as the means of measurement.

·         Ping-pong ball anemometers which are generally home made and are used by students

There are a number of variations of eachanemometer which have been modified by changing certain aspects marginally to be effective in specific areas where wind speed needs to be measured as in open or closed environments. When measuring wind speed the surrounding terrain needs to be taken in to account as well as surrounding buildings or even trees in order to obtain a correct reading.

There are many different anemometers available from hand held anemometer digital readout units to pole and wall mounted units depending on the application but the hand held unit is the most popular unit as it can be taken to various different sites whereas the others are fixed and only read the wind speed in that specific area.