The anemometer is used to measure wind speed and velocity in a variety of applications including for balancing air flow in ducts and tunnels in the HVAC industry. Other industries who rely on anemometers range from sea or plane transportation, construction, and events. Luckily, you can purchase one at any reputable retailer, for example, RS Components.
The anemometer design varies according to its application, though all types perform the same basic function of providing data on wind flow.
Common Anemometer types.
Thermal anemometer
This device, sometimes called hot wire, consists of a fine wire element with a thermistor at the end which reacts to changes of temperature. Readings of wind speed and velocity are based on the speed at which the thermistor cools. These are commonly found placed in regular intervals at cross sections in heating and cooling ducts, and provide measurements used to maintain a balanced air flow.
Vane anemometer
The vane anemometer uses a vertical impeller to measure the speed of the wind. As the wind spins the impeller, the speed is measured by a revolution counter which is electronically converted to wind speed, with the results displayed on an LCD screen.
A telescopic vane anemometer contains a permanently attached vane probe with a telescopic handle providing quick and accurate information about gas and liquid flow. These instruments also use mean calculations to provide data on average volume flow. They are commonly used in HVAC and construction, particularly for roofing, to measure wind direction and gust.
Hand held versions of the rotary vane anemometer are used by firefighters on the field, among others. Wind metres such as the Kestrel 3000 offer functions that include current and average wind speed, maximum wind gust, temperature of air, water and snow, wind chill factor, relative humidity and more.
Cup anemometer
This original anemometer design is believed to have been invented in 1450 in Italy. The cup anemometer consists of three or four cups set horizontally at the top of a pole. The wind will fill a cup, sending it spinning. Wind speed is then taken according to how many times the cups spins per minute. The number of rotations per minute provides the circumference of the anemometer, which is then divided by the number of minutes to give wind speed.
The cup anemometer is ideal for mobile wind speeds and can predominantly be found in use at weather stations.
Ultrasonic anemometer
This instrument measures horizontal and vertical wind speeds using ultrasonic calculations. It consists of two pairs of ultrasonic transducers (devices that convert energy from one signal to another) at a fixed distance. Readings of the time taken for an ultrasonic pulse to travel between the north and south transducers are taken. If wind is blowing the times will alter and calculations are made which provide the exact speed of the wind. The velocity can also be calculated.
Anemometers are a vital tool to detect wind gust, wind speed and velocity. They are used to provide safe working conditions, collect data, and ensure accurate working equipment. Ask your anemometer specialist about the most suitable instrument for your requirements.
