Centrifugal fans are widely classified and can be divided into three types according to different types; one is a low-pressure fan, the other is a Central Asian fan, and then divided into three categories of high-pressure fans, and can be divided into two types according to the blade type. Different applications to choose different centrifugal fans.
The centrifugal fan works by the principle of operation. The rapid rotation of the blades is used to complete the acceleration, so that the flow direction is changed, and the passive conversion to the active is the main factor. When the rotation speed reaches a certain level, the kinetic energy can be converted into pressure energy, the pressure is increased through the impeller, and finally the diffusion process is reached.
The centrifugal fan is essentially a variable flow constant pressure device. In a multistage centrifugal fan, a return flow is used to cause the airflow to enter the next impeller, resulting in higher pressure. When the speed is constant, the theoretical curve of the pressure flow of the centrifugal fan should be a straight line. Due to the internal loss, the actual characteristic curve is curved. For a given pressure and flow characteristic curve, there is a power and flow characteristic curve. When the blower is running at a constant speed, the required power increases with the decrease of the intake air temperature for a given flow rate, and the pressure generated in the centrifugal fan is greatly affected by the change of the intake air temperature or density. .
The centrifugal fan system is composed of a fan and a coil. The general fan unit is placed directly in the air-conditioned room. The air is sucked into the fan, filtered into the fan and heated or cooled by the coil inside the fan, and then immediately sent. In the air-conditioned room, the air conditioner is finally achieved.
The refrigerant used in the fan coil is centrally supplied and is a semi-centralized air conditioning system. In this system, the amount of cold (or heat) is brought into the air-conditioned room by air and water, respectively, which is an air-water system. The fresh air required for the room is usually fed by the pipeline after the outdoor air is concentrated by the fresh air treatment unit.
Air-conditioning fans are flexible and can be placed anywhere in the room, and they are widely used in high-rise buildings such as hotels, apartments, and office buildings. However, this air-conditioning method is only suitable for use under the old building. The advantage is that it takes up less space and can be placed anywhere without the trouble of disassembly.