Duct fans are generally used to remove fumes

In ducted fans, a propulsion arrangement is seen. The duct fans throw the air upwards or in forward motion thereby having an impact on the pressure of air and its velocity. rnDuct fans are generally used to remove fumes, dirt-laden air, steam, hot air and smoke, in many industries or places where these problems are encountered. The advantages of duct fans are many along with its ability and efficiency to supply air for cooling, drying and ventilation.

In following areas, the use of duct fans have been seen-

# Fan Packs

# Aircrafts

# Airships

# Airboats

# Hovercraft

Duct fans are considered to be better as they are far more efficient at higher rotational speed in comparison to conventional propeller. At higher air speeds, they can operate efficiently as through the fan, the designing of duct fan can adjust the air velocity. In comparison to a free propeller a ducted fan has a smaller diameter enhancing its advantages for the same static thrust.

By reducing the tip speed and intensity of the tip vortices, they shield the blade noise hence they are quiet and this is one more major advantage to the kitty of duct fans. On the ground also, they offer more safety.

Though the fan manufactures design fans on the basis of different needs, but some of the design parts are common. Ducted fans usually have an odd number of blades to prevent resonance in the duct. In the design of these fans, temperature is another factor where they have to be built and used.

Due to more and shorter blades, aircraft fans operate at higher rotational speed.

Advantages of duct fans this fan operates more efficiently at higher air speeds make them special. Through the fan, its designer can adjust the air velocity. Some other advantages are that ducted fans do not make much noise, allows a limited amount of thrust vectoring and offer enhanced safety on the ground.

As in case of any product, there are some shortcomings of duct fans as well. Between the blade tips and the duct, they require very small clearances for good efficiency and effective operation. They may be expensive due to the design of these kinds of fans being complex. They require high RPM and minimal vibration which is another problem with them. The weight would still be more even if they are constructed with advanced methods and technique.

As competition between fan manufacturers is increasing day by day better design at lesser cost can result. The focus is on the design but these fan manufacturers also concentrate on issues like energy conservation, energy labeling, performance standards, technology development etc.

Thus, everything in a business that is set up with correct methods and surveys can work out well. In duct fans also, the same principle applies and it has now become a big industry.