# What is the use of square root in Flow measurement?

What is square root extractor? The square root extraction is an electronic or pneumatic device which converts square root signal of the flow transmitter (FT) into corresponding linear FS. The system will produce a 4-20mA signal that is linear with the flow rate.

Square root extractor are usually current operated devices so they can be connected directly in the 4-20mA current loop of a flow transmitter. The output of the square root extractor is again a 4-20mA signal. The flow rate in the pipe work is directly proportional to this signal. The signal from the square root extractor usually goes to a controller which is used to control the final control element.

What is the need of square root extractor in measuring flow?

In flow measurement, a square root extractor is used to convert a non-linear flow signal (e.g. from a flow meter) into a linear signal that can be easily read by a data acquisition system or controller. A square root extractor is used to convert the non-linear signal into a linear signal.

What is the transmitter square root function and why you should use it?

It is a feature on differential pressure (DP) transmitters that uses differential pressure readings to compute process flow.

How is flow measured in square root?

There are numerous different units that can be used to measure flow, depending on the kind of fluid being measured and the goal of the measurement. The most common unit for gauging fluid flow is volume per unit of time. Examples of this unit are cubic meters per second and gallons per minute. One form of flow meter that can be used to monitor flow is a differential pressure flow meter. This kind of flow meter bases its calculation of flow on the pressure difference that exists across a pipe or duct constriction. It is possible to describe the flow in these conditions in terms of the square root of the pressure drop since the flow rate is proportional to the square root of the pressure difference. This is so because the flow rate and the pressure differential are proportionate. The square root relationship is the link between the flow rate through a constriction and the square root of the pressure drop across the constriction. This equation suggests that the flow rate and the pressure decrease at the constriction are inversely related. This relationship between the two variables is described by the Bernoulli equation, which is a key idea in fluid mechanics. The square root of the pressure drop is used to indicate the flow rate as a result.

Why is it important for everyone involved to understand when to apply square root extraction (SRE) for differential pressure transmitter?

Square root extractor is not advisable in keep in transmitter side as the transmitter electronic computational capability is not superior when compared to system. So best practice is to perform the SRE in the controller side.

List few industries which uses square root extractor

Chemical processing, oil and gas production, and water treatment.

Why is a square root extractor required for measuring differential pressure flow?

When using differential pressure application, over 50% of all applications still use DP flow to track flow. This device actually transmits a signal proportional to the differential pressure (P), even if it indicates the flow rate (Q). Because such a system requires a linear relationship or scale, it cannot be used in instrumentation or metering. In actually the differential pressure increases in proportion to the square of the flow rate. We can write this as Differential Pressure (P) is proportional to square of flow rate (Q). In other words square root of Differential pressure (P) is proportional to flow rate (Q). This signal is typically not linearly proportional to the flow rate. Instead, the signal tends to increase as the square of the flow rate. For example, if the flow rate is doubled, the signal generated by the flow meter may increase by a factor of four. This non-linear relationship between the flow rate and the signal can make it difficult to accurately measure and control the flow rate. To overcome this issue, a square root extractor is used to convert the non-linear signal into a linear signal. The square root extractor simply takes the square root of the input signal, which results in a signal that is linearly proportional to the flow rate.

Which type of following flow meters is recommended when measuring slurries and dirty fluids?

The velocity of conductive liquids in pipes, such as water, acids, caustic, and slurries, is measured by magnetic flowmeters. When the liquid’s electrical conductivity exceeds 5 S/cm, magnetic flowmeters can measure accurately.