The cooling fan makes the air flow by inhaling the air body and pumping out the gas, and the heat of the object is exchanged with the outside world to achieve the cooling effect.

The specific suction or extraction of air fan needs to be determined according to the shape of the wind blade and the direction of rotation. Just like an electric fan at home, the fan usually turns clockwise. You can feel the direction of the wind by holding your hands close to the sides of the fan blades.

Because the cooling fan is used in different places and has different shapes, I will take the cooling fan of dry type transformer as an example.

Dry and wet transformer cooling fan

The power transformers we see are generally oil intrusion transformers. In order to strengthen insulation and cooling conditions, the iron core and windings of the transformer are immersed in transformer oil, which is cooled by oil intrusion self-cooling, oil intrusion air-cooling and other ways.

The electric voltage-generator also has a dry type transformer. The core and windings of the dry transformer do not invade the oil, so it cannot be cooled by the transformer oil. Its cooling method is through air cooling, which can be divided into natural air cooling and forced air cooling.

Dry type transformer can be equipped with temperature measurement and control, protection system, through self-measuring winding temperature control fan start and stop.

The cooling fan reduces the temperature of the transformer by increasing the air flow in the winding cooling channel.

In fact, the cooling fan is a large fan used for cooling in special places. Like the electric fan, it reduces the space temperature by increasing the air flow. There is one difference, some fans are pure increase air flow to reduce the temperature, such as dry places, but some fans by reducing the humidity of the body surface to reduce the temperature.

The role of cooling fan, as the name implies cooling fan, must be used for cooling. I take the motor cooling fan as an example. When the motor runs for a long time, the heat will be generated, and the fan will run at this time to blow the heat generated by the motor, reduce the temperature, protect the normal operation of the motor and extend the working life of the motor. It's the same way we blow electric fans when it's hot in summer.

Next we talk about the working principle, first of all, when it will run, in general, it will be designed to run the motor, the cooling fan will follow, there are also cases in the motor installed a temperature sensor, the temperature reaches a certain value, the cooling fan operation. Physically, it works on the same principle as the electric fans we use in the summer. It's very simple. I won't go into detail here.

The working principle is to accelerate the cooling medium flow speed, so that the heat exchange speed is faster, the heat is taken away in time, cooling fans are generally installed on the equipment that is not enough heat dissipation by natural convection of air

The working principle of the cooling fan is that the motor drives the fan blade to rotate at a high speed, and the air flows rapidly in the form of air pumping or air supply, so that the cold air and the heating body continue to exchange heat, so as to realize the cooling of the heating body.

Cooling fans are mainly used in situations where air cooling is required, such as power distribution rooms, high and low voltage distribution cabinets, electronic equipment, distribution cabinets, and computer rooms.