Xin Feng Classroom | Ventilator Series: Differences Between Axial Flow and Centrifugal Fans

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What are the differences between axial flow fans and centrifugal fans?  

1. Different discharge directions: Axial flow fans discharge air along the direction of the shaft, with the inlet and outlet aligned on the same axial line. Centrifugal fans discharge air perpendicular to the inlet direction, enabling 360-degree discharge in any specified direction.

2. Installation complexity differs: Axial fans are relatively simple to install, typically mounted directly on walls or connected to ductwork. Centrifugal fans require more complex installation procedures.

3. Differences in Airflow and Pressure: Axial fans deliver substantial airflow but relatively low pressure, typically ranging from tens to over a thousand Pa. Centrifugal fans, however, offer both high airflow and high pressure. When dealing with ductwork featuring numerous bends, long extraction or supply distances, or significant duct resistance, centrifugal fans are essential.

4. Different Appearance: Axial fans are generally cylindrical in shape, while centrifugal fans resemble a snail shell.

5. Different Motor Connection Methods: The motor of an axial fan is typically integrated within the fan housing. Centrifugal fans feature either direct motor connection or a transmission assembly connection, with the motor located externally. 

 What are the differences in applications between axial flow fans and centrifugal fans?    Axial flow fans and centrifugal fans are two distinct products within the broader category of fans, both primarily serving as equipment for ventilating and exchanging air within an environment. 1. Axial flow fans have extremely broad applications. They operate with airflow parallel to the fan blade axis, such as in electric fans and the outdoor unit fans of air conditioners. They are termed "axial flow" because the gas flows parallel to the fan shaft. Axial flow fans are typically employed in applications requiring high airflow volume but low pressure. They are stationary units that move air through fixed positions. Primarily composed of an impeller and housing, axial fans feature a simple structure but demand highly precise engineering specifications.

2. Centrifugal fans are mechanical devices that utilize input mechanical energy to increase gas pressure and discharge air. They are a type of driven fluid machinery. Centrifugal fans are extensively used for ventilation, dust extraction, and cooling in factories, mines, tunnels, cooling towers, vehicles, ships, and buildings; for ventilation and exhaust in boilers and industrial furnaces; for cooling and ventilation in air conditioning equipment and household appliances; for drying and conveying grain; as air sources in wind tunnels; and for inflation and propulsion in hovercraft.