What is a fresh air system? What is a fresh air system fan?



Xuheng Electronics


Xuheng Electronics

Release time: 2021-09-15


In recent years, with the increasing pollution of urban environment, people are paying more and more attention to the degree of air pollution, and the requirements for air quality are gradually increasing. How can we breathe the clean air of nature in a polluted urban environment Problems that have troubled people for a long time. The emergence of fresh air system has helped people solve this problem. Everyone may be relatively new to the fresh air system, so today I will talk to you about what is the fresh air system and how much is the home fresh air system. I hope everyone will have a clear understanding of the fresh air system after reading the introduction. understanding.
What is the fresh air system, we can take a closer look at the following aspects.
1. Working principle of fresh air system
It is based on the principle that fresh air is sent to the room with special equipment on one side of the closed room, and then discharged from the outside with special equipment on the other side. A "fresh air flow field" will be formed indoors to meet the needs of indoor fresh air ventilation. The implementation plan is to use a high-pressure head, large flow and small power DC high-speed brushless motor to drive the centrifugal fan, rely on mechanical strength to send air from one side to the interior, and force the other side to use the specially designed new exhaust fan to discharge to the outdoor A fresh air flow field is formed in the system. At the same time as the air supply, the air entering the room is filtered, disinfected, sterilized, oxygenated, and preheated (winter). When the exhaust air passes through the host, it exchanges heat with the fresh air, and most of the recovered energy is sent back to the room through the fresh air. Borrowing a large-scale clean space to ensure that the air entering the room is clean. In order to achieve the purpose of indoor air purification environment.
Second, the main advantages of the fresh air system
1) You can enjoy the fresh air of nature without opening the window;
2) Avoid "air conditioning disease";
3) Avoid mold on indoor furniture and clothing;
4) Remove harmful gases that are slowly released after interior decoration, which is beneficial to human health;
5) Adjust the indoor humidity to save heating costs;
6) Effectively exclude indoor bacteria and viruses.
7) Ultra-quiet
3. Main functions of fresh air system
First, renew the indoor air polluted by living and living processes with fresh outdoor air to maintain the cleanliness of indoor air to a certain minimum standard level.
The second function is to increase heat dissipation in the body and prevent discomfort caused by skin moisture. Such ventilation can be called thermal comfort ventilation.
The third function is to cool the building components when the indoor temperature is higher than the outdoor temperature. This type of ventilation is called the cooling cooling of the building.
 Fourth, the basic type of fresh air system
1. Unidirectional flow fresh air system
The unidirectional flow system is a diversified ventilation system based on the combination of central mechanical exhaust and natural air intake based on the three principles of mechanical ventilation system. It is composed of fans, air inlets, exhaust outlets, and various pipes and joints. The fan installed in the ceiling is connected to a series of air outlets through pipes. The fan starts. The indoor turbid air is discharged through the fan through the indoor suction outlet to form several effective negative pressure areas in the room. The indoor air continues It continuously flows to the negative pressure zone and discharges the outdoor. The outdoor fresh air is continuously replenished to the indoor by the air inlet installed above the window frame (between the window frame and the wall), so that you can breathe high-quality fresh air all the time. The air supply system of the fresh air system does not require the connection of the air supply duct, and the exhaust duct is generally installed in the aisle, bathroom and other places where there is usually a suspended ceiling, and basically does not occupy additional space.
2. Two-way flow fresh air system
The two-way flow fresh air system is a central mechanical air supply and exhaust system based on the three principles of mechanical ventilation system, and is an effective supplement to the one-way flow fresh air system. In the design of the two-way flow system, the position of the exhaust air host and the indoor air outlet are basically the same as the distribution of the one-way flow. The difference is that the fresh air in the two-way flow system is sent by the fresh air host. The fresh air host is connected to the indoor air distributor through pipes. The fresh air host continuously sends outdoor fresh air into the room through the pipes to meet the fresh and quality air that people need in daily life. Both the air outlet and the new air outlet are equipped with air volume adjustment valves, which realize indoor ventilation through the power exhaust and delivery of the host.
3. Full heat exchange fresh air system
The total heat exchange fresh air system is an air supply and exhaust system with heat recovery function based on the improvement of the bidirectional flow fresh air system. Its working principle is the same as the two-way flow, the difference is that the air supply and exhaust are completed by a host, and a heat exchange module is added inside the host to quickly absorb heat and release heat, ensuring sufficient heat with the air exchange. The air discharged from the outdoor and the fresh air sent into the room exchange heat in this full heat exchange device, so as to achieve the purpose of recovering cold and heat, saving air conditioning energy. On the basis of improving indoor air quality, minimize the indoor temperature Impact.
4. Ground supply system
Since carbon dioxide is heavier than air, the closer to the ground the lower the oxygen content. From the perspective of energy saving, installing a fresh air system on the ground will get better ventilation. The cold air sent from the air supply port or the upper air supply port at the bottom of the floor or wall diffuses on the floor surface to form an organized air flow organization; and forms a buoyant wake around the heat source to take away the heat. Due to the low wind speed, the turbulence of the airflow organization is smooth, and there is no large vortex. Therefore, the air temperature in the indoor working area is more consistent in the horizontal direction, and it is layered in the vertical direction. The upward wake generated by the heat source can not only take away the heat load, but also bring the dirty air from the working area to the upper part of the room and discharge it through the exhaust vent on the top. The fresh air sent from the bottom tuyere, waste heat and pollutants move upwards under the driving force of buoyancy and air flow organization, so the ground supply fresh air system can provide good air quality in the indoor working area.
Although the air supply has certain advantages, it also has certain applicable conditions. It is generally applicable to the places where the pollution source and the heat source are related, and the layer height is not less than 2.5m. At this time, the dirty air is easy to be taken away by the buoyant wake; there is also an upper limit on the design of the room. If there is enough space for a large air distribution device, the room cooling load can reach 120w / ㎡. If the room cooling load is too large, the power consumption of replacement ventilation will increase significantly and the economy will decrease. The contradiction of taking up space is also more prominent.
It can be seen that, depending on the installation environment of the fresh air system, the choice of fresh air system will be somewhat different. Only by choosing a fresh air system suitable for your own can you achieve the best air exchange effect.
V. Basic classification of fresh air system
Classified by ventilation power: natural ventilation, mechanical ventilation;
Classified according to the location of power: centralized power and distributed power.
6. Main applications of fresh air system
Application range of fresh air system: It is necessary to use fresh air system when someone is in it for a long time and the room is not well ventilated. To sum up, the household fresh air system (using negative pressure ventilation) is suitable for small spaces such as apartments, villas, and baby rooms with fewer ventilations; KTV and Internet cafes with more people's activities and more ventilations Such as entertainment places, machine rooms, hotels, shopping malls, factories, office buildings, restaurants, banks, classrooms, kindergartens, hospital wards and other places, it is best to use new fan units, because of the large number of air changes and energy loss, it is necessary to use heat recovery fresh air system.