The Basics
The most basic answer to the question, “What does a centrifugal fan do?”, is that it moves gas (air), drawing it into the inlet, turning it 90 degrees, and blowing it through the outlet to exit the fan. It moves a higher static pressure than an axial fan, which moves air and gas straight, in one direction. Without air movement inside buildings – whether a room (like in Chet’s example in the video), a house, or an industrial manufacturing facility – things would get dicey. If you were to be trapped in a small room with no ventilation, only breathing in your own exhaled air, you could only survive for so long. Imagine what would happen in a manufacturing facility where there are many other gases and particles at play! If that is all the information on centrifugal fans you were looking for, feel free to stop reading now. For a little more on how they work, carry on.
