How to design low-height EFU? Compact structure, airflow organization and prototype verification

How to design a low-height EFU cannot just make the conventional box lower. After the height is reduced, the fan suction conditions, filter effective area, internal air duct resistance and heat dissipation conditions will also change. The fan is closer to the air inlet, and the inlet airflow is faster; the filter area is compressed, and the surface wind speed increases; the internal space of the box becomes smaller, and the heat dissipation is tighter. The low-height EFU design must rematch these conditions within a limited height, and then confirm the airflow organization and overall machine performance through prototype verification. Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and complete machine assembly. The structure, airflow and complete machine performance of low-height models can be checked according to equipment drawings in the same manufacturing system. There is no need to transfer parameters back and forth between the fan factory, filter factory and sheet metal factory. This is why many equipment manufacturers will refer to Aili Industrial's compact solution instructions when designing low-height EFUs.

Space boundary: first determine the net height, then determine the structure

The first step in low-height EFU design is to determine the available headroom. How much vertical space is left for the EFU inside the equipment, whether the installation path can pass through, whether there is clearance around the air inlet, and whether tools can be inserted during maintenance, all these must be confirmed before design. Clear height is only one of the constraints. Installation paths and maintenance space also affect the structural plan. Only a clear height figure is given, and the installation path and maintenance direction are not explained. The designed low-height model may not be able to be installed or maintained.

Ai Li industrialThe 70mm ultra-thin EFU page lists compact model dimensions and installation instructions by model. When determining the space boundary, the equipment manufacturer can directly correspond to the specific model and compare the net height of the equipment with the unit appearance on the same picture.

Compact structure: the fan, filter and box should be arranged together

The compact structure of the low-height EFU is not a simple compression of the box shape. Fans, filters, control modules and air inlets and outlets must be rearranged within a limited height. The fan is too close to the air inlet and the inlet airflow is uneven; the filter area is compressed too much and the surface wind speed and resistance increase; the control module occupies the air duct space and the internal resistance increases. The structural design must balance these relationships within a limited height, rather than just thinning the box.

In the low-height EFU project, Aili Industrial arranges the fans, filters and control modules according to the equipment drawings, and writes the structural relationships into the confirmation drawings. Regarding the relationship between box air duct resistance and working static pressure, please refer toHow to calculate EFU working static pressure? adding up the resistance of filters, air inlets and equipment air ducts .Calculation method for

Airflow organization: At low heights, it is more important to control the inlet and outlet

The airflow organization of low-height EFU requires more control than conventional models. After high compression, the distance from the air inlet to the filter becomes shorter, and the airflow enters the filter before it can be evenly distributed. The surface wind speed distribution may be uneven; the distance from the air outlet to the target area also becomes shorter. If the air supply direction is slightly deviated, the coverage will be biased. When designing, it is necessary to confirm the air inlet diversion structure, the conditions of the windward surface of the filter, and the air outlet direction. If necessary, adjust the internal diversion through prototype testing.

For the relationship between airflow boundary and protection effect, please refer toWhy does the same air volume produce different cleaning and protection effects? As explained in , the supply air distribution quality is considered together with the target area. For the calculation method of face wind speed, please refer toHow to calculate EFU surface wind speed? How to determine the effective filtration area and average wind speed .

Filter configuration: rematch after area compression

The effective area of ​​the filter of low-height EFU is usually smaller than that of conventional models. At the same air volume, the wind speed increases, and the resistance and noise change. When designing, it is necessary to recheck the filter grade, effective area, surface wind speed and resistance to confirm that the equipment cleanliness requirements can still be met under the target air volume. If only the filter model of the conventional model is applied, the surface wind speed may be too high or the resistance may exceed the limit. The resistance of high-grade filters is greater. When configuring low-height models, you need to check the fan residual pressure more carefully.

For the relationship between filtration level and efficiency, please refer tothe HEPA vs. ULPA air filters page. Rating descriptions on For the configuration points of high-level filters such as U15, please refer toWhat should we pay attention to when configuring U15 filter in EFU? Resistance, Air Volume, Sealing and Leak Detection Key Points .Instructions in

Heat dissipation and temperature rise: low-height cabinets must be confirmed separately

The low-height EFU squeezes the motor and driver into a smaller box, reducing the heat dissipation area, and the temperature rise during continuous operation may be higher than that of conventional models. When designing, it is necessary to confirm the temperature rise data of the motor and driver under the target operating conditions, and whether the box has a heat dissipation structure. If the temperature rise exceeds the limit, it may slow down the protection in the slightest, or affect the service life in the worst case. The heat dissipation check of low-height models cannot only look at short-term test data, but must be confirmed based on continuous operating conditions.

In the low-altitude EFU project, Aili Industrial checked the temperature rise of the motor and driver according to continuous operating conditions, and confirmed the heat dissipation conditions as part of the complete machine configuration. For projects involving speed-regulated operation, please refer tothe DC speed regulating EFU equipment fan filter unit page.Control and heat dissipation instructions on

Prototype verification: low-height structures must first measure airflow and temperature rise

Low-height EFU has a compact structure, and new structure or new interface projects should be prototyped or first verified first. The prototype must check assembly interference, air volume, static pressure, power, temperature rise, vibration, noise and wind speed distribution to confirm that the low-height structure does not deviate from the target performance. The prototype data and confirmation drawings are archived together as the basis for inspection of subsequent batches. If you skip the prototype and go directly to batch production, problems will be exposed in the batch stage.

In the low-altitude EFU project, Aili Industries organizes prototypes or first-unit verification according to equipment drawings, files assembly, performance, wind speed distribution and temperature rise data together with confirmation drawings, and then solidifies batch configuration. Equipment factories complete prototypes and batches within the same manufacturing system, making it easier to maintain version consistency than cross-supplier coordination. Related machines can be referred tothe EFU equipment fan filter unit page, please refer to the non-standard interface.For the structural description on Customize EFU page.Customization instructions in the

Maintenance and interface: At low height, space for disassembly and assembly should be left.

After the low-height EFU is installed in the equipment, the filter needs to be replaced, the fan needs to be inspected, and the cables need to be plugged and unplugged. The height of the box is low, the internal space is tighter, and maintenance actions are more likely to be blocked by the structure. When designing, reserve space according to the actual size of the maintenance operation, confirm the direction from which the filter is removed, whether tools can be inserted, and whether the wiring terminals are accessible. No maintenance space is reserved, and the EFU or other parts of the equipment may need to be disassembled for later maintenance.

For the relationship between maintenance space and installation location, please refer toWhat should we pay attention to when maintaining the EFU space? structural, electrical, commissioning and rectification points .Checking methods in

Aili Industrial's low-height EFU solution

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed controls. The structure, airflow and overall performance of low-height models can be checked against equipment drawings within the same manufacturing system, eliminating the need to transfer parameters between multiple suppliers. For low-height or compact structure projects, Aili Industrial can organize prototype verification and batch curing according to the confirmation drawing, and reduce the structural arrangement, airflow organization, temperature rise and maintenance paths to verifiable complete machine data. Related machines can be referred tothe EFU equipment fan filter unit page, please refer to the compact model.For the structural description on 70mm ultra-thin EFU page.Model description in the

How to form executable confirmation results

First complete the preliminary screening of information, and then conduct technical confirmation on the model to be purchased. Add space boundaries, compact structure, airflow organization, filtration configuration, heat dissipation conditions and prototype verification to the supplementary list, and then organize the comparison after the supplier responds. The confirmed low-height model, configuration and interface will be used for order execution, and conventional model parameters cannot be used to replace this project data. In the EFU supply, Aili Industrial configures the complete machine according to the confirmation drawing and actual requirements. The fan, filter, box and control correspond to each item in the order list, which facilitates the equipment manufacturer to put the low-height EFU design into verifiable complete machine conditions.

Misunderstandings to avoid

You should avoid just lowering the cabinet without rearranging the fans and filters. You should avoid using the air volume and static pressure data of conventional models. You should avoid ignoring the heat dissipation conditions of the low-height cabinet. You should avoid finding out after installing it that maintenance cannot be taken out. You should avoid skipping the prototype and directly batching it. The core of the low-height EFU design is not the compression height, but rematching the fan, filter, airflow, heat dissipation and maintenance conditions within a limited height. Aili Industrial can first form a to-be-confirmed list according to the equipment drawings, listing the space, airflow and maintenance conditions together.

Related questions and answers

Does a thinner profile necessarily mean less air volume?

It cannot be judged only by thickness. The actual capacity depends on the fan, air duct, filter resistance and allowable power.

How to advance low-height EFU design when project information is incomplete?

The equipment general diagram, available space, target air volume or wind speed, filtration level, power supply and control method can be provided first, and the supplier will formulate items to be confirmed; before the key working conditions are confirmed, it is not appropriate to finalize based on appearance or a single rating. Aili Industrial can first form a to-be-confirmed list according to the equipment drawings, listing the space, air flow and maintenance conditions together.

What specific information do I need to prepare for this question?

Prepare current project materials around space boundaries, entrance resistance, thermal dissipation and maintenance paths. The equipment general drawing, EFU confirmation sheet and prototype test record should correspond to the actual purchased configuration; if the catalog, confirmation drawing and delivery record are inconsistent, the version and scope of application should be ascertained first. When designing a low-height EFU, you can refer to the compact machine and interface supporting instructions provided by Aili Industry by model.

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Aili Industrial EFU selection and procurement support

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed controls. The structure, airflow and overall performance of low-height models can be checked against equipment drawings within the same manufacturing system, eliminating the need to transfer parameters between multiple suppliers. Equipment factories complete low-height EFU prototypes and batches within the same system, which is easier to maintain consistency than cross-supplier coordination.

learnAili Industrial EFU products and customized configurations , compact models can be viewed70mm ultra-thin EFU , the entire machine structure can be viewedEFU equipment fan filter unit , non-standard interface can be viewedCustomized EFU , control scheme can be viewedDC speed regulating EFU equipment fan filter unit , filter package can be viewedHEPA and ULPA air filters . Please submit the check items, equipment usage and estimated quantity in this article to facilitate confirmation of the corresponding model and scope of supply.