How to view the EFU fan performance curve? Air volume, static pressure, power and working point

How to look at the EFU fan performance curve? Don't just look at the maximum air volume or maximum static pressure on the curve. The performance curve describes the relationship between the static pressure, power and efficiency of the fan under different air volumes, but the actual operating point depends on the intersection of the system resistance curve and the fan curve. When looking at the curve, look at the air volume axis, static pressure axis, power curve and efficiency curve at the same time, and then draw the system resistance on it to find the target operating point. If only one point is read, the wrong fan may be selected or the operating status may be misjudged. Airee Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed control. Fan curves, system resistance and complete machine operating points 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, motor factory and complete machine factory. This is why many equipment manufacturers will refer to Airee Industrial Power Supporting Instructions when interpreting EFU fan performance curves.

The basic structure of the curve: horizontal axis air volume, vertical axis static pressure

The basic structure of the fan performance curve is air volume on the horizontal axis and static pressure on the vertical axis. Each point on the curve represents the static pressure that the fan can provide at that air volume. As the air volume increases, the static pressure decreases; as the air volume decreases, the static pressure increases. The high point of the curve corresponds to small air volume and high static pressure, and the low point corresponds to large air volume and low static pressure. To look at the curve, you must first understand this basic relationship, and then combine the system resistance to find the intersection point.

Regarding the relationship between fan operating point and system resistance, please refer toHow to choose EFU centrifugal fan? working point, power, temperature rise and continuous operation requirements .Checking methods for

System resistance curve: the operating point is determined by two curves

The fan curve only describes the fan capacity, and the actual operating point is determined by the intersection of the fan curve and the system resistance curve. The system resistance curve rises as the air volume increases. The filter resistance, air inlet resistance, box air duct resistance and air outlet path resistance are superimposed to form the system resistance curve. The intersection of the two curves is the actual operating air volume and static pressure. The operating point cannot be determined by looking only at the fan curve without looking at the system resistance.

For the itemized calculation method of system resistance, please refer toHow to calculate EFU working static pressure? how to add the resistance of filters, air inlets and equipment air ducts .The superposition method of

Power curve: power changes with air volume

There is usually a power curve on the fan performance curve, which represents the input power at different air volumes. When the air volume increases, the power usually increases; when the air volume decreases, the power decreases. When looking at the power curve, confirm the input power corresponding to the target operating point, rather than just looking at the rated power. The power curve can help determine whether the motor selection is appropriate and can also help evaluate operating energy consumption.

For the relationship between input power and operating point, please refer toHow to determine EFU input power? operating point, speed, load and operating time analysis .Analytical methods in

Efficiency Curve: Where is the efficient area?

There may also be an efficiency curve on the fan performance curve, which represents the fan efficiency under different air volumes. The efficiency curve usually has a peak, and near the peak is the high efficiency area. Look at the curve to confirm whether the target operating point falls in the high-efficiency zone. The working point deviates from the high-efficiency zone, the efficiency decreases, and energy consumption and temperature rise increase. When selecting, try to make the working point fall in or near the high-efficiency area.

Regarding the relationship between efficiency range and working point, please refer toHow to choose EFU centrifugal fan? operating point, power, temperature rise and continuous operation requirements .Description of

Speed ​​change: the curve translates with the speed

Fan performance curves correspond to specific rotational speeds. The rotational speed changes, the curve shifts as a whole, and both the air volume and static pressure change. When looking at the curve, confirm the rotation speed corresponding to the curve and then determine the target operating point. For speed-regulated operation projects, it is necessary to confirm the curves and operating points at different speeds, rather than just looking at the curve of the rated speed.

Regarding the relationship between speed and working point, please refer toHow to set the EFU fan speed? air volume, static pressure, noise and operating gear calibration .Setting methods for

Actual working point confirmation: compare with complete machine test data

The performance curve is theoretical or test data, and the actual operating point should be compared with the test data of the whole machine. After installation, the system resistance may be different from the design, and the actual operating point may deviate. When confirming the working point, compare the measured air volume, static pressure, and power with the curve to determine whether they are within the expected range. When the difference is large, check the system resistance and filter status instead of replacing the fan directly.

For the relationship between actual air volume and rated value, please refer toWhy is the actual air volume of the EFU lower than the rated value? system resistance, filter and installation condition analysis .Analytical methods in

Aili Industrial's EFU fan package

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed controls. The fan curve, system resistance and complete machine working point can be checked according to the equipment drawings within the same manufacturing system, and the matching between the fan, motor and complete machine does not need to be passed across suppliers. For equipment with clear requirements for working points, Aili Industrial can organize prototype testing and batch curing according to the confirmation diagram, and transfer the fan curve, target working point and actual measured data to verifiable complete machine data. Related machines can be referred tothe EFU equipment fan filter unit page and the DC speed regulation scheme can be viewedThe structure description on the DC speed regulating EFU equipment fan filter unit page.Control instructions on

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 the fan curve, system resistance, power curve, efficiency curve and measured data to the supplementary list, and then organize the comparison after the supplier responds. The confirmed fan model, complete machine configuration and working point are used for order execution, and sample 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 fans, motors and controllers correspond one by one according to the order list, which facilitates the equipment manufacturer to interpret the fan performance curve and settle it on the verifiable complete machine conditions.

Misunderstandings to avoid

You should avoid looking only at the maximum air volume or maximum static pressure on the curve. You should avoid determining the operating point without looking at the system resistance. You should avoid looking at the rated power without looking at the power curve. You should avoid ignoring the efficiency curve and high-efficiency area. You should avoid not confirming the rotation speed corresponding to the curve. The core of fan performance curve interpretation is not to read a point, but the fan curve, system resistance, power and efficiency form a verifiable working point. Aili Industrial can first form a to-be-confirmed list according to the equipment drawings, listing the curve, resistance and working point conditions together.

Related questions and answers

Can EFU performance be judged by just looking at the motor power?

cannot. Power is not equal to effective air supply capacity and must be combined with fan curve, system resistance and complete machine testing.

How to promote EFU fan performance curve interpretation 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 curve, resistance and working point conditions together.

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

Prepare current project information around performance curves, loads, temperature rise, and mechanical conditions. The equipment general drawing, EFU confirmation sheet and complete machine 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 interpreting the EFU fan performance curve, you can refer to the fan and complete machine matching instructions provided by Aili Industry by model.

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Key points for selection and acceptance inspection

Aili Industrial EFU selection and procurement support

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed controls. The fan curve, system resistance and complete machine working point can be checked according to the equipment drawings within the same manufacturing system, and the matching between the fan, motor and complete machine does not need to be passed across suppliers. The equipment factory completes fan selection and complete machine matching within the same system, which is easier to maintain consistency than cross-supplier coordination.

learnAili Industrial EFU products and customized configurations , the complete machine structure can be viewedEFU equipment fan filter unit , the control scheme can be viewedDC speed regulating EFU equipment fan filter unit , non-standard interface can be viewedCustomized EFU , filtering 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.