Wind turbines have a long history. Many years BC, China had already built a simple wooden huss windmill, which worked on the same principle as a modern centrifugal fan. In 1862, Guibel of England invented the centrifugal fan, the impeller and casing are concentric circles, the casing is made of bricks, and the wooden impeller is made of backward straight blades, with an efficiency of only about 40%, which is mainly used for mine ventilation. In 1880, people designed a snil-shaped casing for mine exhaust air supply and a centrifugal fan with backward curved blades, and the structure was relatively perfect. In 1892, France developed a cross-flow fan; in 1898, the Irish designed a forward blade Sirocco centrifugal fan, which was widely used by various countries; in the 19th century, the axial fan has been applied to mine ventilation and metallurgical industry blasting, but its pressure is only 100~300 Pa, and the efficiency is only 15~25%, until the 40s of the 20th century, it has been developed rapidly.
In 1935, Germany first used axial flow isobaric fans for boiler ventilation and induced air, and in 1948, Denmark made axial fans with adjustable moving vanes in operation, and rotary axial fans, radial acceleration axial fans, oblique flow fans and cross-flow fans have also been developed.
