Fans have a long history. More than 2,000 years ago, countries such as China, Babylon and Persia had already been using ancient windmills to carry water for irrigation and grind grains. After the 12th century, windmills developed rapidly in Europe. In ancient times, China had already manufactured simple wooden windmills for grinding grain, and their working principle was basically the same as that of modern centrifugal fans.
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The first windmills were built in Western Asia - probably in Syria - in the 7th century AD. In this part of the world, there are strong winds that almost always blow in the same direction, so these early windmills were built facing the prevailing wind. They don't look like the windmills we see nowadays. Instead, they have vertical shafts with wings arranged vertically, which is very similar to the wooden horses arranged on a carousel device.
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The first windmills appeared in Western Europe at the end of the 12th century. Some people believe that the soldiers who participated in the Crusades in Palestine brought back information about windmills when they returned home. However, the designs of windmills in the West are quite different from those in Syria, so they might have been invented independently. A typical Mediterranean windmill features a circular stone tower and vertical flanges installed towards the prevailing wind. They are still used to grind grains.
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In 1862, Guebel of the United Kingdom invented the
Centrifugal Fan. Its impeller and casing were concentric circles. The casing was made of brick and the wooden impeller had backward straight blades. Its efficiency was only about 40% and it was mainly used for ventilation in mines.
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In 1892, France developed the cross-flow fan.
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In 1898, an Irishman designed the forward-blade Siloam centrifugal fan, which was widely adopted by various countries.
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In the 19th century, axial flow fans were already applied to mine ventilation and air supply in the metallurgical industry. However, their pressure was only 100 to 300 Pascals and their efficiency was merely 15 to 25%. It was not until after the 1940s that they developed more rapidly.
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In 1935, Germany was the first to use axial flow isobaric fans for boiler ventilation and exhaust.
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In 1948, Denmark developed an
Axial Flow Fan with adjustable moving blades during operation. Swirl axial flow fans, meridional acceleration axial flow fans, oblique flow fans and cross-flow fans;
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Clarage Company, founded in 1874, was acquired by the American Twin Cities Fan Group in 1997 and has since become one of the oldest fan manufacturers. The development of fans has also made considerable progress.
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In 1880, people designed a centrifugal fan with a volute casing and backward-curved blades for mine air supply and exhaust, and the structure was already relatively complete. In 1892, France developed the cross-flow fan.
