Ventilation fans development history

Ventilation fans have a long history. BC for many years had been to create a simple wooden Husker windmill, its working principle and the centrifugal ventilation fans are basically the same. In 1862, the British Kyu Bell invented the centrifugal ventilation fans, impeller, casing concentric type chassis used brick, wood impeller, straight blade, the efficiency is only about 40%, mainly for mine ventilation. 1880, design for mine row air volute casing, and backward curved blade centrifugal ventilation fans, the structure has been perfected. 1892 French for the development of cross-circulation ventilation fans. 1898, the Irish design a forward blade the Xi Luoke type centrifugal ventilation fans, and widely used in various countries; the 19th century, the axial ventilation fans has been applied to the drum of mine ventilation and metallurgical industry wind, but the pressure is only 100 to 300 Pa, only 15 to 25 percent efficiency, rapid development until the 1940s. In 1935, Germany first using axial flow pressure ventilator for boiler ventilation and the wind; 1948, Denmark made the operation of moving the leaf axial ventilation fans adjustable; rotating Axial Flow ventilation fans, Meridian acceleration axial ventilation fans, oblique circulation ventilation fans development and cross-circulation ventilation fans.