A flow meter is a process for measuring the volume or amount of fluid flow flow such as water, gas, or steam. Flow meter itself includes two main devices, namely transmitter (Transmitter) and transducer (Converter). Both devices have relevant roles, but the two components are usually interconnected transducers have a role to feel the flow of fluid (sensing flow) that passes through the main device and the transmitter acts as a signal receiver from the transducer so that it can be translated.
Types of Flow meters that are widely used in the industry to take flow measurements are Ultrasonic flow meter,Electromagnetic flow meter, Coriolis mass flow meter, Orifice Flow Meter, Positive displacement flow meter, Vortex flow meter, Variable area flow meter, turbine flow meter, paddle wheel flow meter, thermal mass flow meter. This type of flow meter has a way of working based on mathematical theory or physics with certain formulations. Using variables obtained based on sensors or others by referring to the laws of the theories found by experts.
How flowmeters work more is based on the type of flow meter, for magnetic flow meters how it works using faraday law. Where magnetic flow meters can only be operated on liquids that have a certain conductivity. Likewise for coriolis mass flow meters, based on coriolis calculations. As for the workings of ultrasonic flow meters, relying on the speed of sound at the ultra level or called ultrasound is able to calculate the velocity of fluid flow.
Flow meters have many types, sizes and models, therefore the type of flowmeter that we will use must be completely adjusted to the needs of applications in the field. Because if the selection of the flow meter type is less precise, it will lead to higher costs. Both because of the age of the flow meter and the accuracy of the results of fluid flow measurements that are not precise resulting in low accuracy.
If you observe the workings of a diverse flow meter, in accordance with the type of flow meter, things such as fluid type, fluid concentration, temperature, acidity of fluid, working pressure, explosion proof environment, even fluid cleanliness must also be informed. This can be used as an initial consideration to determine the appropriate type of flow meter.
Definition of Flow Meter
Flow meter is a device used to measure the volume or mass of a fluid in the form of liquid, gas or solid in a dynamic flow path. The flow of this fluid can be darkly a closed flow as in a pipe or open such as a trench, river or channel.
The most widely known flow meter function around us is for water discharge gauges, calculating pump flow rates, water volume gauges. For PDAM the flowmeter function is as a reference to the amount of water volume that has been used to calculate billing to customers.
Flow meters are called by many terms, namely flowmeter, flow gauge, flow sensor, flow computer, flow transmitter, flow control, flow indicator, flow rate, flow liquid, flow gas, water meter, current meter and others. Tregantung on the type of industry that uses it.
In addition to measuring with the aim of getting accuracy on the calculation of a volume or masaa, flow meters can also be used for control or others. By utilizing the output produced by the flow transmitter that can be in the form of current, contact or data.
How Flow Meters Work
there are various types of ways flow meters work such as velocity flow meters, positive displacement flow meters, mass flow meters, inferential flow meters, and differential flow meters will be discussed as follows:
Velocity Flow Meter
Velocity flow meters use a technique that measures the speed (v) of the calculated flow with the area of the flow path support to get the flow rate. This principle requires a flow that has a laminer character. With characteristics like this required the density of liquid in the sense that in the pipe is required to be fully filled by liquid.
Velocity flow meter readings usually use sensors that produce signals in accordance with the technology used and passed to the transmitter or converte. From this converter or transmitter can be generated flow rate calculations and other outputs such as current and data.
Positive Displacement Flow Meter
Positive displacement flow meters are the only type of flow meters that measure flow volume directly. Fluid will flow in the room with the volume according to the design and moved to another room because of the rotation of the room due to fluid pressure. pressure. The function of the flowmeter room in this type is used to calculate the volume of fluid flowing in the flow meter.
Examples of this type of positive displacement flow meter are Oval gear, nutating disc, diaphragm, helical gear, oscillating piston. The existence of rotation in the flow meter component positive displacement to maintain the stability of the room that is measured sabaiknya used in liquids that have lubricating properties for fluid applications.
The lubricating properties of this liquid are needed to maintain the wear and tear of flow meter components due to friction so that accuracy can be consistent. This type of positive displacement flow meter can only be used in clean and homogeneous fluids to prevent the rotational congestion of the flow meter component.
But for models that use diaphragm valves are usually used in gas fluids such as use in gas meters used at home. But it can be operated at small volumes and small pressures due to the nature of the diaphragm valve itself.
Mass Flow Meter
Long before mass flow meters were applied, mass calculations on mass flow were often calculated from volumetric flow meter output and densitimeter. Density is measured directly, or calculated using the output of the temperature and pressure flow. Measurement of flow mass based on volumetrics is not very accurate.
This is because the changing relationship between pressure and unstable temperature makes density uncertain so that its accuracy is doubtful. The function of a mass flowmeter type is to calculate the mass of a fluid that moves dynamically to be more accurate and efficient.
Long before mass flow meters were applied, mass calculations on mass flow were often calculated from volumetric flow meter output and densitimeter. Density is measured directly, or calculated using the output of the temperature and pressure flow. Measurement of flow mass based on volumetrics is not very accurate.
This is because the changing relationship between pressure and unstable temperature makes density uncertain so that its accuracy is doubtful. The function of a mass flowmeter type is to calculate the mass of a fluid that moves dynamically to be more accurate and efficient.
Inferential Flowmeter
This flow meter does not measure volume, speed or mass, but measures flow by inferring its value from other parameters measured such as pressure differences or the position of the area of the sensor.
Differential Pressure Flow Meter
The principle of operation of Differential Pressure Flowmeters (DP Flowmeters) is based on bernoulli’s equation which describes the relationship between pressure and velocity in a fluid flow. This device guides the flow into a flow barrier (which has a hole with a diameter different from the diameter of the pipe), causing a change in flow velocity and pressure between the upstream and downstream sides of the barrier. By measuring the change in pressure, the flow speed can be calculated.
Flow Meter Component
There are two parts of the main flow meter, namely the flow sensor and flow transmitter or or flow computer. For flow sensors there are several compounds according to the type and model of the flow meter and usually this is the reference size flow meter with a connection adjusted field conditions whether using flange, thread, or others.
For this flow sensor, usually the sensor material is adjusted to the pipe material, fluid specifications, maximum temperature, max pressure, IP class whether it needs water proof or something else, including if needed materials that have food grade and acid resistant.
The second part of the flowmeter is the flow transmitter or flow display or flow gauge, which has the function of translating signals from the sensor into speed calculations and others, which can be displayed in the form of numbers to the display and provide other ouput. Flow transmitters are usually only divided into forms fused with sensors or separate, the term on the ground is compact / integral or remote / split that uses cables as sensor connectors to the transmitter.
From this flow transmitter flow meter is able to read and detect the speed of flow or velocity, with units of distance units per time, aiar discharge or capacity which is often called flow rate with units of volume units per time and can read the volume of fluid passing through the liquid at a certain time with units of volumetric units. And for certain cases the mass flow meter is able to read the mass of the fluid flowing in the flow meter with units of mass units such as grams, kg, tons, punds and others,
Even if a particular model flow meter is combined with temperature then the flow transmitter can present fluid-generated energy that can present a heat energy with joule energy units. This can be applied to steam, hot water in HVAC or on cooling systems such as chillers or air conditioners.
But do not forget for the type of gauge reading or display that uses a mecahnical register system is usually only able to postulate flow rate and volumetric and can not provide analog output unless coupled with a spin sensor that translates the mechanical system rotation into units of volume numbers such as red ssensor or others.
Power dan Output Flow Meter
For the problem of power flowmeter usually on the gauge or reading there are two, namely readings using mechanical registers that use needles that are passed to the number system and there are also digital reading systems. For this type of reading using mechanical registers are often popular with the term regular flow meter, analog flowmeter or manual flow meter. This type of flow meter usually does not use a flow sensor but uses a volume room model such as a rotameter model or pd flow meter. And flow meters with gauge or mechanical register types generally do not require energy power or electricity.
While in the type of digital reading usually uses a sensor system such as magnetic flow meter using sensors in the form of electrode, ultrasonic flow meters can use sensors in the form of ultrasonic transducer, coriolis flow meters using coriolis sensors that are able to read the force that can produce mass flow and so on.
Digital flow meters are usually operated with AC power from 90 VAc to 240 VAc, DC power from 12 VDc to 36 VDc or available also with the use of Batteries that can last up to 2 years – 5 years. Likewise, the output is not only a reading in the display but can also provide analog output of 4 – 20 mA, Pulse, alarem and COMUNIcation RS485. So it is quite complete for those of us who want the results of sensor flow measurement if connected to control, communication to a computer or remote system such as keGPRS or internet system.
Flow Meter Accuracy
The accuracy of the flow meter varies quite differently, according to the type and model of the flowmeter produced. Some have an accuracy of 5%, 2%, 1%, 0.5% and some even 0.2% and better. For the type of cashew flow is usually the expected range if for the quality of the process and product reaches 0.5% to 1%. Meanwhile, if used for irrigation and flow rate monitoring to improve engine performance as in the engine cooling process usually ranges from 2% to 5%.
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Flow Meter function and flow
meter application in the industrial world
In the industrial world such as the automotive industry, the food and beverage industry, the chemical industry, the waste refining industry, the flowmeter function can be used to:
- To assign the flow speed of a fluid in a closed system or pipeline
- Calculate the flow rate or discharge of water in pipes or open streams such as ditches or rivers
- Can check the performance of an engine or pump such as on cooling system, cooling tower or others
- Can to measure and know the volume or mass of a fluid passing through the flow meter
- Flow meters also serve as controls on a process when the output is connected to a plc.
Thus the article “How Flow Meter Works Based on Its Type” Hopefully can answer the reader’s question to the flow meter, hopefully useful.