A centrifugal fan is not just a component. It plays a central role in determining the efficiency, reliability, and safety of industrial processes.

What is a centrifugal fan?

A centrifugal fan is an industrial fan that draws air into a rotating impeller, which transfers energy to the fluid by increasing its velocity and pressure. Air is moved radially thanks to centrifugal force generated by the impeller, accelerating it outward and discharging the flow typically at 90° to the inlet direction. 

It is used in industrial processes where the conveyed fluid may carry dust, operate at high temperatures, or contain aggressive gases. This radial airflow configuration makes centrifugal fans particularly effective for applications requiring medium to high static pressure and reliable performance in harsh conditions.

When evaluating airflow solutions, it is essential to understand the technical differences between an axial fan vs centrifugal fan, as the choice depends entirely on the system's pressure and volume requirements. Every zifeng centrifugal fan series is engineered to meet these specific operating requirements with configurable designs.

Centrifugal fan working principle

Understanding how a centrifugal fan works starts with its three main components: the impeller, the casing (scroll or volute), and the inlet.

•  Inlet: air enters axially, drawn in by the low-pressure zone created at the impeller eye as it rotates.

•  Impeller: the rotating blades accelerate the air radially outward, imparting kinetic energy through centrifugal force.

•  Volute casing: this component collects the high-velocity air and progressively slows it down, converting velocity pressure into static pressure.

•  Discharge: air is expelled at 90° to the inlet, at significantly higher pressure than at entry.

Key characteristics and dimensions

Centrifugal fans are defined by high-pressure performance and stable operation under variable loads. A common technical query concerns centrifugal fan dimensions: these are not fixed but are strictly related to the impeller diameter and the specific series. Zifeng fans range from small units (500 mm) to large-scale industrial installations exceeding 2,450 mm in diameter. 

Main features:

•  Radial discharge: air or gas is expelled outward at 90°, allowing effective static pressure generation;

•  Stable operation: maintains consistent behaviour under variable load conditions;

•  Heavy-duty construction: built for environments with dust, high temperatures, or corrosive substances

Efficiency and performance curve

The efficiency of a centrifugal fan describes how effectively it converts shaft power into useful work on the fluid. Typical centrifugal fan efficiency at the Best Efficiency Point (BEP) ranges from approximately 70% to 85% for backward-inclined and airfoil blade designs.

•  Flow rate (m³/h): volume of air moved per hour.

•  Static pressure (Pa): resistance the fan can overcome.

•  Best Efficiency Point (BEP): operating away from the BEP increases energy consumption and introduces unnecessary mechanical stress.

Centrifugal fan installation considerations

Correct installation is as important as correct selection. The principal considerations are covered in:

•  Inlet conditions: disturbed or swirling inlet flow significantly reduces performance. Straight duct runs of at least 2–3 diameters upstream are generally recommended.

•  Vibration isolation: anti-vibration mounts or flexible connections prevent structural transmission of fan-generated vibration.

•  Alignment (belt-driven units): misaligned drives  reflect on premature bearing and belt failure.

•  Balancing: impellers must be dynamically balanced to the appropriate grade before installation and re-checked after any repair involving material removal.

•  Commissioning checks: rotation direction, motor current at full flow, bearing temperature, and vibration levels should be verified at  firstly start-up.

 ZIFENF FAN provides complete turnkey installation assistance for all fan types and related accessories, ensuring correct execution on site.

ZIFENG FAN: primacy centrifugal fan suppliers

Our company has the ability of scientific research, development, design, manufacturing, installation and commissioning, and has experienced technical personnel. In the East China fan manufacturing industry, we took the aim to pass the IS09001:2015 quality assurance system certification and have the export EU CE certification, and with high quality products and hard work spirit to win the trust and praise of the majority of users!