How to match the air volume and static pressure when FFU and high-efficiency air supply vents are used together?

Direct answer: First determine the air supply volumes of the two types of terminals, and then check the pressure sources respectively. FFU needs to confirm the air supply capacity of the whole machine under the target air volume after installing the specified filter; the high-efficiency air supply outlet needs to confirm whether the upstream air conditioning unit and air duct system can deliver the designed air volume to the end under the target resistance. Finally, it is necessary to verify the airflow distribution and room pressure difference when the two types of air supply work together.

FFU comes with its own fan, and efficient air supply outlets usually rely on centralized systems for air supply. When the two are mixed, a misunderstanding is easy to occur: if the equipment with 'qualified air volume' is selected separately, the total air volume in the room is deemed to be qualified. In fact, if zone divisions, resistance and return air paths are not coordinated, local supply air or room airflow balance may still deviate from the design.

First create an air volume distribution table

On the floor plan and ceiling diagram, indicate the cleaning target, target air supply volume, air supply end and return air position area by area. Depend onThe air volume borne by the FFU fan filter unit and the air volume borne by the high-efficiency air supply outlet should be listed separately, and then the overall air supply and return balance of the room should be checked.

The purpose of this table is to give each part of the design air volume a clear source to avoid double counting or omissions.

Find their respective work points respectively

When selecting FFU, it depends on its assembly project specificationHEPA or ULPA filter at designed operating gear and target air volume. Performance after Maximum air volume and maximum static pressure cannot be directly paired; the measurement location and test conditions of the static pressure in the data should be confirmed.

For high-efficiency air supply outlets, the actual air volume that can be obtained by each branch of the centralized air supply system after bearing the resistance of the air duct, filter and terminal should be checked. When replacing filters or adjusting terminal configurations, branch air volumes may need to be rebalanced.

Check whether when one end changes, the other is affected

FFU speed adjustment will change the air supply volume in the area it is responsible for; centralized system adjustment will also change the air supply status of high-efficiency air supply outlets. Although the two have different power sources, they jointly affect the return air, airflow direction and pressure difference relationship in the room. Therefore, a mixed scenario should test the planned operating conditions, not just the situation where all equipment is running at full capacity at the same time.

If the FFU project requires zone speed regulation, it can be planned during the design stage.FFU group control system coordinates the air volume distribution between control zones and efficient air supply outlets.

On-site acceptance to see the overall results

The actual air supply volume of FFU and high-efficiency air supply outlets should be measured on site, and then the airflow distribution, cleanliness and pressure difference in relevant areas at key process locations should be checked. If the total air volume is qualified but the local effect is insufficient, the end position, air volume distribution and return air path should be checked instead of just increasing the air volume of a certain type of equipment.

Aili Industrial can match the complete machine configuration of the FFU based on the target air volume, filtration requirements, installation dimensions and control requirements of the area the FFU is responsible for. For batch projects, it is recommended to confirm the working point of the prototype first, and then write the air volume distribution, test conditions and acceptance methods into the technical agreement. Specific performance is subject to on-site test results.

The most worthwhile thing to ask the supplier when selecting a model is: 'After this FFU is assembled with the specified filter for the project, what is the performance data under the target air volume, and how are the test conditions defined?' This is a better way to judge whether the solution is suitable for the actual project than asking about the maximum air volume or maximum static pressure alone.