This series of fans is a new type of selected engineering ventilator. The series is characterized by high efficiency, low energy and low noise. It is suitable for ventilation of large, medium and small tunnels. It can also be applied to infrastructure construction such as rivers, water conservancy, railways, subways and civil air defense. The fan consumes less energy, has low noise, is easy to maintain and is light, and is the preferred fan for ventilation such as tunnel construction.