How vacuum cleaners work

Although this may seem like a very complicated machine, the conventional vacuum cleaner is actually made up of six essential ports: an intake port, an exhaust port, an electric motor, a fan, a porous bag and a housing that stores all other components.

When you plug the vacuum into the socket and turn it on, here's what happens:

• 1. First, the electric current will run the motor, which is connected to the fan, which looks like an airplane propeller.
• 2. As the blades begin to turn, they will force the air upward toward the exhaust port.
• 3. When the air particles are driven forward, their density increases in front of the fan and therefore decreases behind it.

The pressure drop that occurs behind the fan is similar to the pressure drop when you take a drink with a straw. The pressure level in the area behind the fan will fall below the pressure level on the outside of the vacuum cleaner.

This will create a vacuum inside the vacuum cleaner. Ambient air will blow into the vacuum through the inlet, as the air pressure inside the vacuum is much lower than the outside pressure.

Pick up dirt

The airflow generated by the vacuum is similar to a stream of water. Moving air particles rub against dust or debris and if it is light enough, friction will transport the material inside the vacuum cleaner.

As dirt continues to enter the exhaust port, it passes through the dust bag. The tiny holes in the vacuum bag are large enough to let air in, though too small for dust particles to enter. As a result, when the air stream enters the bag, dirt and debris are collected.

You can stick the bag anywhere along the path between the intake tube and the exhaust port, as long as the air flow passes.

Suction

The suction power of a vacuum cleaner depends on several factors. Aspiration may be stronger or weaker depending on:

• 1. Fan power - To generate a strong suction, the motor must rotate at a good speed.
• 2. Airflow - When a lot of debris builds up in the bag, the air will have to deal with a higher resistance level than the outlet. Each particle of air will move slowly due to the increase in drag. That's why a vacuum cleaner works a lot better once you've replaced the bag than when you've been using it for a while.
• 3. Intake Port Size - Since the fan speed is constant, the amount of air that passes through the vacuum cleaner per second is also constant.