Electric fans have become an essential part of our lives. It provides a cooling effect during the summer and rainy seasons. Do you know how does it work?
An electric fan is a device which converts electrical energy into mechanical energy. It works on the basis of magnetic effects of electrical currents.
The heart of an electric fan is an electric motor. So before understanding the working of a fan, it is essential to know the working principle of an electric motor.
In its simplest form, it consists of a coil or armature through which the current flows. It is connected with a spindle. This coil is placed in between the poles of a magnet. When the electric current flows through the coil, it starts rotating due to the magnetic effects of electric current. This motor consists of a split-ring commutator to which two carbon brushes are attached. The armature of the motor is connected to a metal shaft. At the other end of the shaft, three or four blades made of a light metal are attached which also start rotating along with the motor. These blades are designed in such a way that when they rotate, they suck in air from one side and throw it to the other side, thus causing strong air currents.
The speed of rotation of the motor can be controlled by controlling the current which is done with the help of a regulator. This regulator consists of a resistance which controls the amount of electricity flowing through the coil.
Usually electric fans are of two types: ceiling fans and table fans. The domestic electric fans are usually rated from 60 watts to 120 watts.
A third type is often used in underground establishments, kitchens, cinema halls, stores etc. to expel the polluted air. These are called exhaust fans. The blades of these fans are so designed that they suck in the air from inside and throw it outside. These are also used in air coolers.
Now the question arises as to how the air of the fan gives us the cooling effect? The fan increases the speed of air currents and this brings about an increase in the rate of evaporation. Since evaporation causes cooling, a running fan produces a cooling sensation.