Whether they’re the ones you have at home or in your laptop, Fans have one job: to cool off their surroundings and move air. They’re handy, efficient, and easy to use.
The idea seems simple enough: you have a device with a motor and several rotating blades. Yet, do you know how a fan works?
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We were curious about it ourselves, so we decided to do a bit of research to help us get to the bottom of it. Then, we put together all our findings in a reader-friendly, accessible outline.
Let’s take a look.
How Does an electric ceiling Fan Work?
Basically, for a fan to work, it has to convert electrical energy into mechanical energy, which gets the surrounding air to cool down. Then, as this cool air moves away from the fan, it heats up and rises.
When this happens, it gets pulled in once again by the fan, which then cools it back down. This regular circulation of air is how fans are able to create a nice, comfortable breeze.
Another way to put it is that fans increase pressure levels behind them while reducing the air pressure in front of them. This difference in pressure gets the air around the fans to move and circulate, making it feel less stifling.
It’s important to mention that fans don’t actually lower the air temperature in the room. Instead, they simply create a constant current of air.
Having uninterrupted airflow circulating the room helps reduce humidity levels and evaporates moisture, which is how we feel cooler. This phenomenon is what experts call the ‘evaporative cooling’ effect.
Here’s a step-by-step breakdown of what happens when you turn on a fan.
Step 1: You plug in the fan and turn on the on/off switch.
Step 2: AC current travels through the wires and heads straight for the start capacitor.
Step 3: The capacitor takes the electrical energy and transports it to the stator windings.
Step 4: The stator windings use the energy to build up a rotating magnetic field within the motor.
Step 5: This energy is carried from the motor to the housing via the axle and ball bearings.
Step 6: The rotating movement forces the rotor and housing to spin in the same direction.
Step 7: The housing rotates, and so do the blades attached to it, which creates a cooling effect.
Parts of a Fan
You’ve just read a detailed, step-by-step process by which a fan can create a cool breeze. Now, it’s time to learn more about each of the parts mentioned above and their specific functions.
Capacitor
Start capacitors are the fan components that help store energy. They’re also what helps turn this stored energy, or potential energy, into mechanical or kinetic energy. This kinetic energy is how the fan shifts from a rest state to an operational state.
The way it does that is that it increases the electric fan motor torque. Accordingly, this allows the motor to revolve at various speeds and power modes.
Axle
The axle, or shaft, is a steel metal rod. It connects the motor and capacitor to the housing.
Axles have two jobs. The first one is that they play a hand in transferring alternating electric current (AC) from the capacitor to the stator windings.
Their second job is to help support the ball bearings. To do this, they have to stay motionless. This state of rest allows the other parts around it to do their jobs better and more efficiently.
Ball Bearings
Ball bearings are round, rolling elements with steel or ceramic balls inside. The balls help maintain adequate spacing on the bearing races, which are typically made from bearing quality, high-carbon chromium alloy 52100 steel.
These are small, but fundamental, components of many appliances, including the fan. They serve two primary functions: they help carry the load and support the rotation of the fan’s moving parts.
They work by linking the axle to the housing, thus helping to provide a rotary motion. Even at maximum speeds, ball bearings are designed to help reduce friction and excessive heating.
Stator Windings
Stator windings are found in the fan motor. They refer to the thousands of turns carried out on a conducting wire on a non-conducting structure, such as a coil.
They have low resistance, which means they’re great conductors of energy. It also means that stator windings could possibly be the most critical part of the fan. After all, they’re responsible for transforming electric current into a magnetic field.
Rotor
Rotors are half-circular attachments found in the electric motor of the fan. It’s basically the magnet that takes the electrical energy and helps convert it into mechanical energy.
In general, standard fans are usually comprised of two pieces of magnets, or rotors. Yet, some have only one, while others have as many as three rotors, depending on the fan’s size and capacity.
Housing
As the name implies, the housing is where you’ll find the stator, rotor, and axle rod. Ball bearings are also part of the inner elements of the housing.
Then, on the outer side of the housing are the blades.
Blades
Also called the ‘wings,’ blades are the hanging parts attached to the outer part of the housing. When the blades rotate, they push on the air molecules around them.
This movement effectively transfers the blades’ kinetic energy to the air molecules, dispersing them around the entire area. As the air molecules disperse and break apart, they create a cooling effect.
Most fans have three blades, though they may differ in length and degree of angle. Blade designs mainly depend on the motor’s size and capacity.
Some fans don’t have blades and work slightly differently.
To Sum Up
So, how does a fan work? It’s simple, really, when you think of it.
Fans work by reducing the air pressure of the molecules in front of them. Then, they carry that hot, high-pressure air away and to the back, where they then suck the hot air back in.
This in-and-out motion of the air particles creates a pressure difference, which helps create an evaporative cooling effect.
Fans have a lot of applications in our home. From cooling our electronics to making sure that mold doesn’t grow in our bathroom. We have discussed how you can repair a bathroom fan here.
There are a lot of fans. In this post, we have discussed how they work.
