1. How to calculate the air volume of high-efficiency air supply vents?

The air volume of an efficient air supply outlet usually needs to be determined based on the designed air supply volume of the clean room, rather than first determining the air volume of an air supply outlet and then working backwards for the entire clean room.

For cleanrooms designed with air changes in mind, the following basic formula can be used:

Total air supply volume of clean room = room volume × number of air changes

The calculation formula is:

Q = V×N

in:

• Q: The total air supply volume required in the clean room, in m³/h

• V: clean room volume, unit is m³

• N: Number of air changes, unit is times/h

For example:

A clean room has a length of 10m, a width of 8m, and a height of 3m.

Room volume:

V = 10 × 8 × 3 = 240m³

If the design adopts an air change rate of 30 times/h:

Q = 240 × 30 = 7200m³/h

Then, the total designed air supply volume of the clean room is approximately 7200m³/h.

If a high-efficiency air supply outlet of 500m³/h is used, the theoretical quantity can be as follows:

7200 ÷ 500 = 14.4

In actual projects, we cannot simply round up according to 14.4. It also needs to be determined based on the actual working air volume of the air supply outlet, air flow organization, room layout, filter resistance and design margin.

2. What are the main parameters to consider when calculating the air volume of high-efficiency air outlets?

The calculation of air volume for high-efficiency air supply outlets generally requires the following parameters:

Therefore, in actual projects, the design conditions of the clean room should be determined first, and then the number of efficient air supply outlets and the air volume of a single air supply outlet should be determined.

3. In addition to the number of air changes, can it also be calculated based on the air supply speed?

Can.

For some clean areas that use unidirectional flow or have clear design requirements for air supply speed, the air volume can be calculated based on the air supply area and design wind speed.

The basic formula is:

Q = A × V × 3600

in:

• Q: Air supply volume, m³/h

• A: Effective air supply area, m²

• V: average air supply speed, m/s

• 3600: Conversion factor between hours and seconds

For example, the effective area of ​​a certain air supply area is 2m², and the designed average air supply speed is 0.3m/s:

Q = 2 × 0.3 × 3600 = 2160m³/h

This calculation method is more suitable for scenarios where the air volume is determined based on face wind speed and air supply area.

Therefore, there is not only one method for calculating the air volume of high-efficiency air supply outlets, and it needs to be judged according to the design method of the clean room.

4. How to calculate the number of high-efficiency air supply outlets?

After the total air supply volume of the clean room has been determined, the number of efficient air supply outlets can be further calculated.

The basic formula is:

Number of air supply outlets = Total design air supply volume of the clean room ÷ Design air volume of a single air supply outlet

For example:

The total designed air supply volume of the clean room is 6000m³/h, and the designed air volume of each high-efficiency air supply outlet is 500m³/h.

Theoretical quantity:

6000 ÷ 500 = 12

Therefore, you can make a preliminary arrangement according to 12.

But this is only the first step in calculating quantities.

Actual design also needs to consider:

• The location of the air outlet on the ceiling

• Column network and equipment location

• Return air outlet location

• Air flow organization inside clean room

• The spacing between air supply vents

• Actual working air volume of a single air outlet

• High efficiency filter resistance

• Duct system resistance

• Fan residual pressure

• Later filter resistance changes

Therefore, it is usually necessary to comprehensively check the air volume and air outlet layout in engineering design.

5. Is the larger the air volume of the high-efficiency air outlet, the better?

no.

The air volume of high-efficiency air supply vents should match the clean room design requirements.

If the designed air volume of a single air outlet is too large, higher air supply speed and system static pressure may be required, which will also affect the air outlet layout and indoor air flow organization.

If the air volume of a single air outlet is too small, the number of air outlets may need to be increased, resulting in a denser ceiling layout and increased air duct connection and installation workload.

Therefore, the reasonable selection idea is:

Clean room design conditions → Total air supply volume → Design air volume of a single air outlet → Number of air outlets → Air outlet layout → Air duct and fan verification

6. What is the relationship between the air volume of the high-efficiency air supply outlet and the HEPA filter?

High-efficiency air supply vents are usually used in combination with HEPA filters, so the air volume calculation also needs to consider the resistance of the filter.

Air will create resistance when passing through the filter, and as the filter age increases, the filter resistance may change.

Therefore, we can’t just look at the theoretical air volume of the tuyere, we also need to pay attention to:

Design air volume + initial resistance + final resistance + fan static pressure

In the actual selection process, if the filter specifications have been determined, the air supply outlet should be matched based on the filter's rated air volume and resistance data.

For clean systems using HEPA or ULPA filters, the actual working conditions also need to be determined based on the specific filter model.

7. A complete example of calculating the air volume of high-efficiency air supply outlets

Assumptions:

• Clean room length: 10m

• Clean room width: 8m

• Clean room height: 3m

• Design air exchange rate: 30 times/h

• Design air volume of a single high-efficiency air outlet: 500m³/h

The first step is to calculate the room volume:

10 × 8 × 3 = 240m³

The second step is to calculate the total air supply volume:

240 × 30 = 7200m³/h

The third step is to calculate the number of theoretical tuyere:

7200 ÷ 500 = 14.4

Therefore, the number of air outlets and the air volume of a single air outlet can be recombined according to the engineering design.

For example, the air volume can be allocated to different numbers of air supply outlets based on ceiling size, equipment layout and air flow organization, rather than mechanically rounding to 14.4.

8. In actual projects, should the total air volume be calculated first or the high-efficiency air supply outlet should be selected first?

It is recommended to first calculate the total designed air supply volume of the clean room, and then determine the specifications and number of efficient air supply outlets.

Recommended process:

Clean room size → Design cleanliness level → Determine the design method → ​​Calculate the total air supply volume → Determine the air volume of a single air outlet → Determine the number of air outlets → Air outlet layout → Check the air duct and fan

This can avoid directly selecting the air outlet according to a certain standard air volume, while ignoring the air organization of the entire clean room.

9. How to select air volume for Aili industrial high-efficiency air supply vents?

Aili Industry isIn the high-efficiency air supply outlet project, matching can be made according to the clean room's space size, designed air supply volume, filter specifications, installation methods and on-site conditions.

The selection of efficient air supply vents not only involves the box size, but also involves:

• Air intake method

• Static pressure box structure

• High efficiency filter specifications

• Filter sealing method

• diffuser

• Ceiling installation dimensions

• Air duct connection method

• Design air volume

• System static pressure

Aili Industrial has bothHEPA high efficiency filter、ULPA ultra high efficiency filter、FFU、EFU , blower, motor andProducts such as control systems and manufacturing capabilities can be combined and matched according to project requirements when supporting terminal air treatment equipment.

For specific clean room projects, it is recommended to provide the room length, width, height, cleanliness level, design air volume or number of air changes, and ceiling installation conditions, and then confirm the specifications and quantity of efficient air supply outlets.

10. Frequently Asked Questions about Calculating the Air Volume of High-efficiency Air Supply Inlets

1. Can the air volume of the high-efficiency air outlet be calculated directly as 500m³/h?

500m³/h can be used as the design air volume of a single air outlet for preliminary calculation, but the total design air supply volume of the entire clean room needs to be determined first.

2. Is the number of high-efficiency air supply outlets equal to the total air volume divided by 500?

If the design air volume of a single air outlet is 500m³/h, the 'total design air supply volume ÷ 500' can be used to calculate the theoretical quantity, but the actual quantity needs to be adjusted based on the air outlet layout and air flow organization.

3. What is the relationship between the air volume of high-efficiency air supply outlets and the cleanliness level?

The cleanliness level will affect the design air supply conditions of the clean room, but a fixed air volume cannot be determined directly based on the cleanliness level alone. It also needs to be combined with factors such as room size, process characteristics, and airflow organization.

4. The greater the air volume of the high-efficiency air supply outlet, the fewer air outlets are needed?

From a mathematical calculation point of view, after the air volume of a single air outlet increases, the theoretical number of air outlets may decrease, but in the end, the air supply speed, air flow organization, filter specifications and ceiling layout still need to be considered.

in conclusion

The core of calculating the air volume of high-efficiency air supply outlets is to first determine the total design air supply volume of the clean room , and then determine the quantity based on the design air volume of a single air outlet.

Common calculation methods include:

Air exchange rate method: Q = V × N

as well as:

Supply air speed method: Q = A × V × 3600

The actual project cannot just look at one formula, but also needs to be comprehensively selected based on the cleanliness level, room size, air flow organization, HEPA filter, air duct resistance and installation conditions.