Is the minimum fresh air ratio the minimum ratio of fresh air volume to total supply air volume?

Yes. The ratio of fresh air introduced to the total treated air volume in the total air mixing system is the fresh air ratio.

For example, 10,000 air volume air handlers, of which 1,500 cubic meters of fresh air and 8,500 cubic meters of return air are introduced. Then the fresh air ratio is 15%.

Fresh air volume refers to the fresh air introduced into the room from the outside, which is different from the indoor return air. Fresh air volume is an important criterion to measure indoor air quality, fresh air volume directly affects the circulation of air, the degree of indoor air pollution, grasp the indoor fresh air volume, ensure indoor air governance, and create a good and healthy indoor environment.

Yes. I used to be exposed to the fresh air industry, but now I have less contact with it. From the past few years of my practice, I would like to express my own views on the current ranking of major brands and brands, for reference only

1.Sender: Like radiators, the first to enter China, first-class brand, first-class **, there are special new fan companies abroad, there are pure imported new fans, and the system design is different from most companies, the average family should not consider it, I think it is super expensive.

2.LANSHE, France: Mainly do heat pumps, the equipment is good, but mainly in Shanghai activities, ** is also high.

3.Japan Panasonic: The host is made in China, ** is OK, the cost performance is good, but the wind pressure of the domestic equipment is not enough, just pay attention to the installation.

4.Honeywell: Large companies, there are too many types of operations, and domestic equipment should be better than purely domestic.

5.Mitsubishi: Japanese company, rigorous, equipment is not bad, but the industry is large, not very professional.

6.Yadu: a large domestic manufacturer, suitable for the taste of the Chinese people, although the product is average, but ** is very suitable for Chinese consumption, the average family can be considered.

7.Huandu: The big domestic manufacturers are similar to Yadu, and the equipment is more realistic.

8.Other foreign brands: German Yibiter, German Weta, Spanish Saint Road,

9.Beijing Odeo, other companies in Shenzhen, a lot, not much attention.

3. Dear, hello, I am glad to answer for you how much is the air volume of the fresh air outlet, which is the best value of the air speed of the air outlet, and the maximum value is not more than 4m s. According to the national standard, the number of air changes per hour for ordinary residential buildings is 1 time, and the per capita fresh air volume index of domestic residential buildings is not less than 30m3 h. Therefore, the size of the fresh air volume of the fresh air system should be the size of the slag in the room, and the range is generally within 2 meters per second!

The fresh air outlet is an air outlet that introduces air from the outside, and the air is introduced from the outside, and is sent into the room through the processing (filtration, sterilization, heat exchange) of the fresh air outlet to increase indoor oxygen. The first kind of sound-absorbing cotton: glass fiber sound cotton, sound absorption coefficient (NRC) = can effectively absorb audio noise above 1000Hz in the pipeline, the sound absorption effect is relatively good, and has little impact on wind resistance.

The second kind of sound-absorbing cotton: Jinzita sound-absorbing cotton, sound-absorbing coefficient (NRC) =, can effectively absorb audio noise above 1000Hz in the pipeline, and the sound absorption effect is relatively good, which has a greater impact on wind resistance. The third type of sound-absorbing cotton:

The new sound-absorbing material foam aluminum sound cotton, sound absorption coefficient (NRC) =, can effectively absorb the audio noise above 1500Hz in the pipeline, the sound absorption effect is strong, and the wind resistance is not great. The best value of the air speed at the air outlet, the maximum value does not exceed 4m s. The air volume of the fresh air system is not as large as possible.

Legal analysis: The calculation of fresh air volume in the air-conditioning area and air-conditioning system shall comply with the following provisions:

1) The amount of fresh air required by the personnel should be determined according to the activities and work nature of the personnel, as well as the length of stay in the room.

2) The fresh air volume in the air-conditioned area shall be determined according to the maximum value of the fresh air volume required for air dehumidification, which is not less than the sum of the fresh air volume required for compensating the exhaust air and maintaining the air pressure in the air-conditioning area, and the fresh air volume required for fresh air dehumidification.

3) The fresh air volume of the all-air air-conditioning system, when the system serves multiple air-conditioning areas with different fresh air ratios, the system fresh air ratio should be less than the maximum value in the fresh air ratio of the air-conditioned area.

4) The fresh air volume of the fresh air system should be determined according to the cumulative value of the fresh air volume of the air-conditioning area or system served.

Legal basis: Article 2 of the Standardization Law of the People's Republic of China The standards (including standard samples) mentioned in this law refer to the technical requirements that need to be unified in the fields of agriculture, industry, service industry and social undertakings.

Standards include national standards, industry standards, local standards, group standards, and enterprise standards. National standards are divided into mandatory standards and recommended standards, and industry standards and local standards are recommended standards.

Mandatory standards must be enforced. The State encourages the adoption of recommended standards.

The inlet air volume accounts for about 75% of the exhaust air volume.

Smoke exhaust equipment: the circulation of air per unit time, there are other subdivisions such as air supply volume, fresh air volume, etc., and the air supply volume is used to indicate the capacity of ventilation equipment such as blowers, and the unit is cubic meters of seconds. Because of the large volume, the air volume of the fan can reach tens of thousands of cubic meters per hour.

Fresh air volume refers to the total amount of fresh air in the room. China's national standard GB T1883-2002 stipulates that the fresh air volume should not be less than 30m3 hPerson.

The inlet air volume accounts for about 75% of the exhaust air volume.

Is there a relationship between the wind pressure and the air volume of the fresh air system?

The actual air volume of the total air volume of the system is larger than the design air volume, and it is more common that the total air volume is smaller than the design air volume. The design air volume needs to be calculated according to the use, area, number of people, heat load and other factors of the building, and the actual air volume is usually affected by various factors such as installation quality, maintenance, air tightness and so on. If the total air volume of the buried system is too large, it will cause unnecessary waste and energy loss; However, if the total air volume of the system is too small, it will cause the indoor air to be turbid, too warm or too cold, which will affect the quality and comfort of the indoor environment.

Therefore, it is necessary to make reasonable adjustments and optimizations according to the design standards and actual conditions to ensure that the total air volume of the system can meet the design requirements.

The main function of the air supply volume is to bring the indoor load to the air conditioning unit, and then the heat exchanger in the air conditioning unit will bring this part of the load to the cooling or heating equipment, and then bring it to the outside by the cooling water system or consume a certain amount of energy to heat the air.

In other words, the supply air volume is determined according to the indoor load.

The fresh air volume is based on the hygiene requirements of indoor personnel, and its main role is to supplement fresh air and dilute the concentration of harmful substances.

The design code generally stipulates that the proportion of fresh air volume in the total air supply volume shall not be less than 10%.

Since the fresh air volume replenished in the air-conditioning season requires a certain amount of energy, the total amount (or proportion of the total air supply) should not be too large.

The calculation is not very easy to calculate, and the measurement is okay under certain conditions.

I don't know what the concept of air supply volume you are talking about, most of the fresh air of the new fan refers to the air that the system really introduces into the room.

The measurement and calculation of air volume is the wind speed multiplied by the area of the tuyere, pay attention to the unit conversion. Sometimes it is inconvenient to calculate the area of the air outlet, such as irregular, for example, the inside is small and the outside is directly larger, etc., you can add a container, a large waterproof bag and the like, and then add a flange at the air outlet, the area at this time is regular, and the wind speed of the tuyere is also uniform.

If the air volume is calculated during the design, it will not be very accurate, because the use of the filter screen of the filter level, air duct structure, etc. will cause the internal wind resistance and design parameters to be inaccurate, most of them are approximate, and they are measured after the design is completed.