The working principle of the shut off fan, what is the principle of the fan

The shut-off fan is used to install the discharge port of the discharger working under negative pressure, and the upper part accepts the material discharged by the discharger, and relies on the rotating impeller to play the role of conveying materials, and also plays the role of sealing, preventing air from being sucked in from the discharge port during pneumatic conveying, and ensuring the normal discharge of the discharger.

The shut-off fan is also called discharger, airlock valve, and rotary valve, which is divided into three categories: ordinary type, pressure-resistant type, and high-temperature resistant type.

Features of shutting down the fan.

1. Adopt elastic impeller and enhance flexible sealing to eliminate impeller jamming.

2. The outer side of the bearing seat displacement valve body isolates the dust particles directly, prolongs the service life of the bearing, and facilitates maintenance.

3. Equipped with cycloidal reducer, reliable structure, stable and compact.

4. Equipped with reducer, reliable structure, stable and compact.

There are three types of shut-off fans: ordinary type, pressure-resistant type, and high-temperature resistant type.

Ordinary type: It can be used on the usual materials below 80 degrees and at room temperature, it can continuously and evenly supply materials to the conveying pipe, and it can be used as a discharger function in the system and the separation dust collection department.

Pressure-resistant type: it adopts a closed rotor, which can be widely used in suction and pressure-fed airflow conveying systems and negative pressure conveying equipment, which can ensure that the airflow pressure in the conveying pipe does not leak, and can safely convey and collect materials, so it is called ten thousand airlocks in this regard, which can not only withstand pressure, but also have ordinary functions.

High temperature resistant type: according to the temperature rise of the material conveying and the discharge port, because the temperature has an impact on the expansion of the body, as well as the bearing and oil seal system is not good, our factory has designed a high-temperature resistant external structure shut-off fan, which separates the running part from the box part in contact with the material, and can safely put the bearing operation and the oil seal system without being affected by the temperature and work normally, such products are not only resistant to high temperature, but also can be aimed at the temperature absorption of materials and metal.

The conveying and acceptance of powder has a very good effect because this kind of object has penetration, penetrating the oil seal device material directly into the bearing, resulting in the operation of the machine without damaging the machine, it is the characteristics of the exterior, it will not contact with the material.

The shut-off fan is an improved impeller open type air shut-off, which is constructed with an impeller, shell, end cover, bearing, plexiglass cylinder (with or without as needed) and other parts of the pulling mechanism, its upper end is connected with a flange and the discharge port of the discharger, accepts the material discharged from the discharger, and excludes the material from the bottom in the continuous rotation process of the impeller.

The impeller adopts the open type, which not only plays the role of preventing blocking and stopping the plug, but also reduces the weight and reduces the appearance.

The fan is a machine that relies on the input mechanical energy to increase the gas pressure and discharge the gas, and it is a driven fluid machine. There are two types of blowers, one is called "centrifugal blower", its principle is that when the fan is working, the fan impeller inside rotates at high speed, so that the air in the fan casing produces centrifugal force and is thrown off the fan impeller, and is "pressed" to the fan outlet through the air outlet; At this time, because the air around the fan impeller is thrown out and the "negative pressure" is generated, the "new air" is continuously replenished from the air inlet, which constitutes the normal working state of the fan;

The second type is called "axial fan", its working principle is: because this fan is the same as the electric fan, the surface of the blade and the fan shaft have an angle, when rotating, the blade will "push" the air along the axis to the air outlet, and a certain negative pressure is formed at the air inlet, and the new air is also replenished, so as to maintain the normal working state.

As the name suggests, a fan is a mechanical device that extracts or supplies air.

The working principle of the fan is to input electric power and drive the fan impeller to rotate through the motor to achieve the effect of suction or exhaustion of the gas.

The fan is composed of air inlet, impeller, shell, motor and other components.

The motor converts electrical power into mechanical power to drive the impeller to rotate.

The air inlet is used to guide the smooth flow of gas into the impeller.

The impeller is to transfer the kinetic energy during rotation to the gas and convert it into fluid power, which is expressed as the air pressure and air volume.

The casing collects the gas blown out of the impeller and controls the flow direction of the gas.

Abstract: What is the principle of a fan? The working principle of the fan is basically the same as that of the turbine compressor, but due to the low gas flow rate and the small change in pressure, there is generally no need to consider the change of gas specific volume, that is, the gas is treated as an incompressible fluid.

Below, let's take a look at the working principles of 3 types of fans. 【Working principle of fan】What is the principle of the fanWhat is the working principle of the 3 types of fansThe principle of the fan:

Fan is a machine and a defeated machine that relies on the input of mechanical energy to increase the gas pressure to guide the flow of gas, and it is a driven fluid machinery. The working principle of the fan is basically the same as that of the turbine compressor, but due to the low gas flow rate and the small change in pressure, there is generally no need to consider the change of gas specific volume, that is, the gas is treated as an incompressible fluid.

According to the flow direction of the air flow into the impeller, the fan is divided into: axial fan, centrifugal fan and oblique flow (mixed-flow) fan.

1.Centrifugal fan.

The gas flow enters the rotating blade channel, where the gas is compressed and flows in the radius direction under centrifugal force.

According to the principle of converting kinetic energy into potential energy, the centrifugal fan uses a high-speed rotating impeller to accelerate the gas, and then decelerates and changes the flow direction to convert kinetic energy into potential energy (pressure). In a single-stage centrifugal fan, the gas enters the impeller axially, changes to radial as it flows through the impeller, and then enters the diffuser. In a diffuser, the gas changes the direction of flow causing a deceleration, which converts kinetic energy into pressure energy.

The increase in pressure occurs mainly in the impeller and to a lesser extent in the expansion process. In a multistage centrifugal fan, a reflux is used to bring the air to the next impeller, creating a higher pressure.

2.Axial fans.

The fan that flows axially in the direction of the axis after the air flow enters the fan blade yard shed Huilun in the flow path of the rotating blades. Compared with centrifugal fans, axial fans have the characteristics of large flow rate, small volume and low pressure head, which should be paid attention to when used in dust and corrosive gas occasions.

When the impeller rotates, the gas enters the impeller axially from the air inlet, and is pushed by the blades on the impeller to increase the energy of the gas, and then flows into the guide vane. The guide vanes deflect the gas flow into axial flow, while the gas is directed into the diffuser tube, which further converts the kinetic energy of the gas into pressure energy and finally into the working line.

3.Diagonal flow (mixed-flow) fans.

In the impeller of the fan, the direction of the air flow is between the axial flow type, and the flow is approximately along the cone, so it can be called an oblique flow (mixed-flow) fan. This type of fan has a higher pressure coefficient than an axial fan and a higher flow coefficient than a centrifugal fan.

When the impeller rotates, the gas enters the impeller axially from the air inlet, and the Bailey beam is pushed by the blades on the delayed impeller to increase the energy of the gas, and then flows into the guide vane. The guide vanes deflect the gas flow into axial flow, while the gas is directed into the diffuser tube, which further converts the kinetic energy of the gas into pressure energy and finally into the working line. Types of fan coil unit models

There are many types of fans, and their working principles are different; 1.According to the classification of production materials: iron shell fan (ordinary fan), FRP fan, plastic fan, aluminum fan, stainless steel fan 5 categories.

2.According to the direction of gas flow, it can be divided into four categories: centrifugal type, axial flow type, oblique flow type (mixed flow type) and cross flow type.

Centrifugal fan principle: The fan is made according to the principle of centrifugal force, and the air flow flows axially into the impeller of the fan and then along the radial direction. Its products include centrifugal fans, centrifugal blowers and centrifugal compressors.

Axial fan principle: The air flow enters the impeller of the fan axially and flows approximately along the axis direction on the cylindrical surface. Its products include axial flow fans, axial flow blowers and axial flow compressors.

Principle of rotary fan: use the rotor rotation to change the volume of the air chamber to work. The main products are roots blowers, rotary compressors, etc.

3.According to the flow direction of the air flow into the impeller, it is divided into three categories: axial flow fan, centrifugal fan and oblique flow (mixed flow) type.

4.According to the use, it can be divided into three categories: press-in local fan (referred to as press-in fan), flameproof motor placed outside the runner or in the runner and flameproof motor in the explosion-proof sealing cavity (referred to as extractable fan) 3 categories.

5.According to the form of pressurization, it is divided into three categories: single-stage, two-stage and multi-stage pressurized fans.

6.According to the pressure, it is divided into three categories: low-pressure fan, medium-pressure fan and high-pressure fan.

7.According to the outlet pressure (boost), it is divided into three categories: fan (10,000 PA), blower (10,000 PA), compressor (350,000 PA).

Hehe, there are hundreds of combinations together, and the working principles are different.

We at Lingnan Automation have fans, and you can find their information on the Internet.

The schematic diagram of the fan is shown in the following figure:

Fan: Fan is the customary abbreviation of gas compression and gas delivery machinery in China, and the commonly referred to fan includes ventilator, blower, and wind turbine. Gas compression and gas conveying machinery is a machine that converts rotating mechanical energy into gas pressure energy and kinetic energy, and transports gas out.

The main structural components of the fan are impeller, casing, air inlet, bracket, motor, pulley, coupling, silencer, transmission parts (bearings), etc.

The unpowered ventilator uses the natural wind force and the air heat convection caused by the temperature difference between indoor and outdoor to push the turbine to rotate, so as to use centrifugal force and negative pressure effect to discharge the stale hot air in the room.

The fan is related to the energy consumption of the system and is a very critical part of building energy saving. According to the National Air Conditioning Equipment Quality Supervision and Inspection Center, many fans have problems under rated working conditions, so it is necessary to produce and manufacture fans in strict accordance with product standards.

As the name suggests, a fan is a mechanical device that extracts or supplies air.

The working principle of the fan is to input electric power and drive the fan impeller to rotate through the motor to achieve the effect of suction or exhaustion of the gas.

The fan is composed of air inlet, impeller, shell, motor and other components, and the motor converts electrical power into mechanical power, drives the impeller to rotate the air inlet, and guides the gas to enter the impeller smoothly.

The impeller is to transfer the kinetic energy when rotating to the gas, convert it into fluid power, and express it as the air pressure and air volume casing, which collects the gas blown out of the impeller and controls the flow direction of the gas.

The working principle of the fresh air system is as follows: the fresh air system circulates the indoor air through pressurization technology, on the one hand, the indoor dirty air is discharged outdoor, and on the other hand, the outdoor fresh air is sterilized, disinfected, filtered and other measures before being input into the room, so that the room is fresh and clean air all the time. The details can be seen in the figure below.

Take the Yunjing fresh air system, which is more popular during this time, for the first time, the turbocharged engine technology of the car is used for fresh air purification, and the air that is about to be discharged is recycled back into the room through heat ** and purification, which not only increases the circulation of indoor air, but also increases indoor pressure, forming a micro-positive pressure environment to prevent pollutants from invading through the gaps in doors and windows.

Relatively speaking, turbo technology is a relatively strong point in innovation, using hot and cold dual channels, supporting dual channel purification, single channel purification, dual channel purification fresh air three operating modes, which perfectly solves the problem of "one-way flow inlet air cooling two-way flow air volume" of traditional technology.

In terms of filtration, mainly according to the different indoor and outdoor pollutants, the dual-channel filtration of fresh air channel and purification channel is used for targeted optimization, and through 5-6 stage tower filtration, the removal rate is 99%, and the removal rate of sulfur dioxide (soot odor) is 95%. The fresh air volume reaches 300 cubic meters per hour, and the purification capacity reaches 600 cubic meters per hour. The photocatalyst reaction formed by its 254nm wavelength ultraviolet rays sterilizes and degrades the activated carbon garbage bin, which avoids the secondary pollution caused by the traditional activated carbon adsorption method that cannot really kill bacteria and viruses and degrade formaldehyde and other decoration pollution, excessive adsorption or bacterial breeding after moisture absorption.

Since the 254nm wavelength ultraviolet light is standard for sterilization in hospitals, it has a strong sterilization ability to ensure that no ozone is generated.

The working principle of axial fans.

Axial fans get their name from the fact that fluid flows from the axial direction to the impeller and flows out in the axial direction. Its working principle is based on the leaf airfoil theory:

The gas consists of an angle of attack. When entering the impeller, a lift force is generated on the wing back, and at the same time a force of equal magnitude and opposite directions is generated on the wing belly, which causes the gas to be discharged from the impeller in a spiral shape and move forward in the axial direction. At the same time, the gas is continuously sucked in at the inlet of the fan due to the effect of the pressure difference.

For the axial fan with adjustable moving blades, the larger the angle of attack and the larger the perimeter of the wing back, the greater the lift, the greater the pressure difference of the fan, and the smaller the air volume. When the angle of attack reaches a critical value, the gas will leave the profile of the wing back and vortex will occur, resulting in a significant drop in fan pressure and stalling.

The fluid in the axial fan is not affected by centrifugal force, so the static pressure energy that rises due to centrifugal force is zero, so the energy head it produces is much lower than that of a centrifugal fan. Therefore, it is generally suitable for places with large flow and low head, and belongs to the high specific speed range.