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The air source for SmartFlow SC1

Why is the measured low pressure calculation still valid with the FCU?

If we consider the resolution of a measuring device such as a voltmeter, the measurement accuracy will be greater at large deviation rather than low deviation.

We say: "we must use the smallest range possible".

Ex: resolution = 1 graduation.

Hence the measurement accuracy obtained from 1/100 (1%) at full scale and 1/10 to 10 graduations (10%)



In the case of the FCU its resolution is 1/1000.

So for a full scale measurement of 100 mbar we have an accuracy of 0.001 / 100 ( 0.001% ).

For a measurement at 10 mbar (1/10 of the full scale) we obtain an accuracy of 0.001 / 10 ( 0.01% ).

Which remains very satisfying!

  • A good shop vacuum is the simple, inexpensive device to power the SmartFlow SC1 Kit that provides a great way to achieve a professional precision computerized flow bench.

  • While a high powered air source can be constructed for flow testing at constant regulated test pressures, a shop vacuum can provide highly relevant flow test data that is comparable to that. obtained with powerful and regulated sources.
    The sensitivity and precision of the FCU electronic processor, compliance with ISO 5167-2, and the software's ability to efficiently estimate flow rates at non-constant test pressure in real time, make this possible.

    So why deprive yourself of an inexpensive solution, low consumption, fully integrated, compact, less noisy that represents the  off-the-shelf vacuum cleaner?

  • When looking for a shop vacuum for your blower, make sure of the features:

    • 40mm flexible hose (to fit directly to the supplied 63-40 fitting), or larger with a suitable adapter

    • A blower outlet (for exhaust mode)

    • The size that suits you best

  • Automotive engine parts are typically tested at a test pressure of 10 or 28 inches of water (25 or 71 mbar). Although the FCU can accurately estimate flow rates from a lower test pressure down to flow rates of 71 mbar or more (up to 100 mbar) without any problem, you can test the flow as close as possible. 25 or 71 mbar. Very powerful shop vacuums will allow you to test at higher test pressures than a less powerful shop vacuum. This is why you can either use a very powerful vacuum cleaner or couple two vacuum cleaners via a double elbow or double branch connected to SmartFlow.

Flow rate scaling

Air flow data scaling has long been used by scientists as a practical means of testing reduced models for aerodynamic properties using wind tunnels. As the construction and testing of a full-scale model may not be possible, scale tests provide valuable data that can be used to estimate full-scale data (aviation, architectural structure...).

We can benefit from the advantages of scaling flow data by using a lower power flow bench.

SmartFlow processor and software can estimate your data from the low power bench at a lower or higher test pressure in real time. Scaling up flow data for low power bench like SmartFlow is not new or a gadget. SmartFlow's resolution and accuracy can provide data that can be surprising and comparable to high pressure flow testing.The flow data shown here illustrate an example of scaling the SmartFlow SC1 bench data with a 1000 W workshop vacuum (Karcher WD3 premium).

The blue measured flow curve corresponds to the data recorded by the FCU SmartFlow. You don't see any significant change in flow once the valve lift reaches 4mm. This is what an operator would see if they did not employ a SmartFlow flow processor to scale the data to a given test pressure (10 inches H2O in this case). If this data were collected from a liquid pressure gauge, the data line would appear even flatter. This is because the FCU SmartFlow has a resolution of 1/1000 . It is at least 10 times more sensitive than most high quality liquid manometers that would be suitable for use on a flow bench, or any other digital manometer with a resolution of 1/100.
The orange curve is the actual data scaled or corrected to 10 inches of water (25 mbar) by the SmartFlow software. Now you can easily see that there will be a drop in flow after an 11mm valve height, and the flow starts to saturate at a 7mm lift. The user can derive valuable information from this example: linear zone, saturation zone, etc.

In addition to this, you need to know more about it.

The SmartFlow package has the sensitivity to perform efficient scaling of flow data. This provides amateurs and professionals alike with an inexpensive, compact and low-power solution for flow testing comparable to high pressure testing ...

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