How Do Blower Fans Work?

How Do Blower Fans Work?  

Blowers are important tools. When you’re shopping for blowers to do a specific job, you’ll find the options abundant. Choosing the right blower might feel like a large task, but when you know more about how they work, the task becomes more manageable. While blowers are varied, pretty much all of them work on the same principle. That principle is simple enough, and when you see how it works, you can understand how different mechanisms impact the functionality of the blower. 

The Basics of a Centrifugal Fan

Blowers primarily work through the concept of a centrifugal fan. This is fundamentally different from a blade fan or propeller fan. Instead, they use what are known as impellers to move air radially. Whereas a normal propeller fan will move air axially, the radial flow of air in a blower allows for different design options. You can have multiple stages of air movement, and centrifugal fan designs can create incredibly high pressures and flow rates. Centrifugal fans will also create an angle in the flow of air, eliminating the need for long, straight lines in the air-movement system.

Impellers can come in a number of orientations, but the idea is pretty simple. If you have ever fanned the pages of a book and felt air move, then you have used the concept of impellers. When they are scaled up to industrial applications, they are rigid, curved blades that can rotate very quickly.

Impellers are typically driven by an electric motor. This can be done directly or through a drive belt. Direct motors tend to be better for high-pressure blowers while belt drives are more common among low-pressure volume blowers. 

Belts and Drivers

The driving mechanism of a blower fan largely determines its application. When you attach a belt to the motor, you allow for variable speed operations. This is better for lower pressure situations. The belts also reduce strain on the fan itself, making belt drives preferable for operations that take longer. The additional points also commonly make belt-drive blowers easier to repair.

When the fan is directly driven by the motor, you get more power to the fan at the cost of greater strain. These fans typically have to be made of stronger, more costly materials. The advantage is that they can run at much higher RPM and create more pressure. They can also move a larger volume of air faster. This makes them common in many utility blowers as well as high-pressure systems.

Centrifugal fans are adaptable and powerful, and that is why they are found in virtually all blowers. They can be used for countless functions, and they can be optimized for each of those functions. They are an invaluable resource for any application that needs to move air, whether it is for cooling, ventilation, drying, inflating or otherwise.