There are sickle type, trapezoidal type and AVC patent folding type. Relatively speaking, the sickle-shaped fan blade runs smoothly and quietly, but the wind pressure it can generate is also small; Trapezoidal blades are prone to generate large wind pressure and noise. Folding is the best design, which can generate large wind pressure while keeping low noise, but it is only used in AVC's own products at present. At present, sickle-shaped design is more common.
Well-designed blades can produce large output air volume and wind pressure at low fan speed, and at the same time, they will not produce too much wind noise. In addition to the shape, the angle of blade inclination is also very important, and the design should meet the characteristics of motor and the needs of heat sink. Otherwise, simply pursuing the big blade inclination angle may lead to the situation of small wind and strong wind.