How to determine FFU specifications and quantity for clean corridor projects?

Direct answer: First determine the zoning air supply requirements based on the corridor's cleanliness requirements, length and width, door location and traffic conditions; then select an FFU that can be installed in the ceiling and achieve the target air volume under the specified filter and design resistance. The quantity should be initially calculated based on the zone air volume and confirmed through corridor layout, adjacent room airflow balance and on-site testing.

Clean corridors are often long and narrow and connect multiple process rooms. The passage of people and materials, the opening of doors and the position of return air will all affect the air supply effect. Therefore, the FFU specifications and quantity cannot be determined simply by dividing the corridor area by the area of ​​a single piece of equipment, nor can they be directly calculated using the product's nominal maximum air volume.

First divide the corridor into areas that require air supply

The project should clarify the cleanliness level of the corridor, the purpose of connecting rooms, the location of doors, the frequency of transportation and the target air flow direction. Longer corridors can be segmented according to functions and operating conditions, and the target air supply volume and cleanliness requirements are determined respectively.

The pressure difference relationship between the corridor and adjacent rooms should be checked together with the overall air supply and return plan.FFU provides filtered air supply, but the pressure difference is also affected by the return air, exhaust air and door opening status. Increasing the number of FFU does not mean that the pressure difference must reach the standard.

Then select the single FFU specification

First check the ceiling module, available height, beam position, lamps and maintenance space, and select the size that can be installed. Then view the FFU assembly specificationHEPA or ULPA filter .Effective air volume, static pressure and power consumption under design operating gear and resistance conditions after

Specification selection should take into account corridor width and air supply distribution. Under the same total air volume, the layout effect of a small number of large-sized FFU and a large number of small-sized FFU may be different, and it needs to be judged based on the location of the door, corner and return air.

The quantity is initially calculated based on the air volume, and then revised based on the arrangement.

For each corridor partition, the required air supply volume of the partition ÷ the effective air volume of a single FFU under the design working conditions can be used to initially calculate the quantity, and the result is rounded up. Then put the FFU into the ceiling plan and check whether the air supply is reasonably distributed along the corridor and whether there are obvious weak areas at doorways and corners.

If the quantity meets the total air volume, but beams, lamps or access openings cannot be avoided, the specifications and arrangement should be adjusted. If the arrangement is complete, but the local air supply or air flow direction does not meet the requirements, the FFU location, return air path or zone air volume should also be re-evaluated.

Use prototypes and field testing to finalize solutions

For batch projects, it is recommended to first confirm the prototype size, filter configuration, performance under the target air volume, and maintenance methods. After installation, the actual air volume, wind speed distribution, cleanliness and pressure difference relationship with adjacent rooms in each zone are tested according to the technical protocol. The test results are the basis for correcting the FFU operating gear, position and quantity.

Longer corridors also allow for advance planning of power supply and control zoning. When unified speed regulation and status monitoring are required, they can be combinedThe FFU group control system determines the communication interface and partition mode to facilitate subsequent debugging and maintenance.

Aili Industry can match the FFU complete machine specifications and batch configuration based on the corridor floor plan, ceiling conditions, cleaning targets, filtration requirements and control needs. The specific quantity and performance should be subject to the project technical agreement and actual working condition test results.

Q: Can the number of corridor FFU be calculated based on area only?
Answer: The area can only be used for preliminary arrangement. The zoning air volume, door position, return air path and on-site air flow performance should also be checked.

Q: The larger the air volume of a single FFU, the smaller the quantity required?
Answer: Air volume is only a condition for quantity calculation; it must also meet the air supply distribution and installation requirements along the corridor.

Q: What information should be provided when consulting Aili Industrial?
Answer: It is recommended to provide the floor plan and ceiling diagram of the corridor, the use of adjacent rooms, the location of doors, cleanliness and pressure difference requirements, target air volume, power supply and control methods.