The working principle of centrifugal air blower known as a centrifugal fan is quite different from conventional air blowers. Considering their designs, the blower exhibits a radial airflow pattern to increase the volume and pressure of air.
These are things you need to about centrifugal blowers:
What is a Centrifugal Blower?
A Centrifugal Air Blower is a simple machine used to increase the volume and pressure of airflow through a specific duct. The blower uses its blades rotating inside its central axis to draw air inside the casing and move the air centrifugally according to its casing design, the action will increase the volume of airflow while the narrowed opening at the exit point will help the outgoing air to buildup pressure.
Applications of Centrifugal Blowers
The areas of application of centrifugal blowers include;
Foundry Industries for fire blowing and oxygen supply
Confined space jobs for the supply of fresh air
Hair salons for drying of human hair
Steel bars Rolling mills for furnace air supply
Hospitals for cleaning and clean air supply, etc.
Design features of Centrifugal Air Blowers
Though centrifugal air blowers can come in different centrifugal shape designs, the most common is the squirrel-cage or hamster wheel shape. Consider a centrifugal air blower shape as the shape of a car tire pulled out from its wheel and then has both sides covered while an opening is made by the side of the tire. The center of the tire has a shaft running through both sides of the tire and the shaft is carrying the blades or impellers. The impellers have a very close range with the walls of the inside of the tire. One end of the shaft is connected to an electric motor that will be rotating the impellers or blades inside the tire. Depending on the impeller or blade design, openings will be created at one end of the tire to enable the impellers or blades to suck in the air and discharge it through the opening at the side of the tire, which is the basic design for centrifugal air blowers.
However, the design illustrations mentioned above can be altered slightly to obtain specific results depending on the designer. For instance, the shape of centrifugal air blower use in hair salons has a slight variation in shape and size to the centrifugal air blowers used in the heating of furnace but the two have the same working principle.
Additionally, the centrifugal blower can also come in the shape of a drum with central rotating impellers that transmits energy to the sucked air and force it to leave through the duct by the side of the drum.
The Working Principle of Centrifugal Air Blowers
Centrifugal air blower is an energy converting machine that converts the kinetic energy of the rotating impellers to the sucked air in it and causes it to acquire pressure and volume before discharging it. The exiting air from its ducts can have up to a hundred times speed and fifty times pressure to the atmospheric pressure and speed of the air entering into the blower.
The blower circulates the air radially at 90 degrees and exits the air radially during the cause of impellers or blades rotations. At the opening by the side of the blower, the air will be forced to exit but due to space constriction and a large volume of air in circulation, the exiting air will have pressure. The speed of the electric motor and the size of the impellers helps to increase the air volume and pressure.
Do not block the suction opening of the blower because it could stop the blower from blowing out air.
Do not remove the guard at the suction to avoid taking in flying objects like waterproof.
Do not insert a stick or object into the blower impellers while in operation.
Position the blower properly before operating it.
The blower couplings should be tightly fixed to ensure safe working operations.
Regular cleaning of impellers and airways
Regular changing of bearings whenever necessary
Airways should not be blocked when the blower is in operation
Regular painting of the external and internal bodies of the blower prevents corrosion and rust.
The greasing of bearings and dynamic parts can help to smoothen its operations.
Do not use unsuitable screws and nuts to tighten the parts.
Take note of changes in sound to know when to stop the blower
Once any part of the impeller or blade starts touching the wall of the casing, it is an indication of misalignment. The blower impellers/blades need to be aligned.
Once you notice unusual vibration from the blower, stop it and check for misalignment problems as well as bearings problems.
If the blower refused to operate check the electrical connection to the electric motor and check the electric motor itself.