Technical Deep Dive: Centrifugal Jet Fan vs. Axial Jet Fan
Published on by EMVEE Corporation Pvt. Ltd.
Centrifugal vs. Axial: Choosing the Right Jet Fan Technology for Your Project
When specifying a jet fan for a tunnel or car park, engineers face a critical choice: should it be an axial or a centrifugal jet fan? While both are used for impulse ventilation, their internal mechanics and performance characteristics are quite different, making each suitable for specific scenarios. Understanding this jet fan vs axial fan comparison is key to an optimal system design.
The Axial Jet Fan: High Thrust, Linear Flow
The axial jet fan is the most common type. As we've discussed, it functions like a propeller in a tube, creating a powerful, long, linear jet of air.
- How it Works: Air is drawn in and discharged parallel to the motor's axis.
- Best For: Long, open spaces like tunnels or large, rectangular car parks where the primary goal is to push air in a straight line with maximum jet fan thrust.
- Characteristics: High velocity, high airflow volume, but moderate pressure development.
The Centrifugal Jet Fan: High Pressure, Directed Flow
The centrifugal jet fan offers a unique advantage in more complex situations.
- How it Works: Air enters the fan axially (along the motor shaft) but is then slung outwards at a 90-degree angle by a centrifugal impeller. This creates a lower, wider, but higher-pressure jet.
- Best For: Areas with low ceiling heights, complex geometries, or obstacles. The high-pressure discharge can "stick" to the ceiling (due to the Coandă effect), allowing it to travel further without being obstructed. It is the preferred centrifugal type jet fan for applications requiring air to be pushed around corners or into specific zones with more force.
- Characteristics: Lower velocity than axial fans, but significantly higher static pressure capability. This makes them ideal for overcoming resistance.
Head-to-Head Comparison
| Feature | Axial Jet Fan | Centrifugal Jet Fan |
|---|---|---|
| Airflow Pattern | Long, narrow, high-velocity jet | Wide, lower-velocity jet |
| Pressure | Moderate | High |
| Ideal Ceiling | High ceilings | Low ceilings, complex layouts |
| Thrust | Maximized for linear distance | Effective for navigating obstacles |
| Primary Use | Tunnel ventilation, large open car parks | Car parks with low headroom, specific zone ventilation |
Making the Right Choice
The decision is not about which fan is "better," but which is right for the application. For a straightforward tunnel project, an axial jet fan in tunnel is often the answer. For a basement car park with tight spaces and structural beams, the centrifugal jet fan provides a more effective and controlled solution.