Just like other industrial and domestic fans, centrifugal blowers are available in a variety of designs.
Perhaps the most fundamental variant is the single-stage fan vs the multi-stage model. Single-stage fans contain only one set of impellers and are the ideal choice for steady, fixed airflow. By contrast, multi-stage fans contain two or more impeller wheels, allowing the creation of a variable airflow for more complex uses.
Ventilation fans, normally installed in ceilings or upper walls, feature either an upblast or downblast design. Upblast fans are typically used to pull gas, fumes and air pollutants out of a particular location - for example a restaurant kitchen, factory or laboratory. Downblast models, meanwhile, pull air into a location for cooling purposes.
Consider the following factors when choosing a centrifugal fan:
- Pressure requirements
- The airflow required
- The temperature of the site the fan will operate in - warmer locations may require a more powerful fan
- The altitude of the operation site
- The type of environment in which the fan will operate. Will the incoming air be clean, polluted, dry or wet?
A wide range of centrifugal fan speeds are available, measured in rounds per minute (rpm). Typical speeds start around 780 rpm and can go as high as 40,000 rpm. Higher speed fans produce a stronger airflow for demanding industrial environments.
Other types of blower include: