How Do Flow Meters Work - Flowmeter Types And Principles

How Do Flow Meters Work - Flowmeter Types And Principles
Flow meters are devices that are used to measure the flow rate of a certain liquid or gas. They can measure these substances in terms of the volumetric flow rate or the mass flow rate. The volumetric flow rate is generally given in m3/second. The mass flow rate is given in kg/second.

by Adrian Fletcher

Flow meters are devices that are used to measure the flow rate of a certain liquid or gas. They can measure these substances in terms of the volumetric flow rate or the mass flow rate. The volumetric flow rate is generally given in m3/second. The mass flow rate is given in kg/second.

There is a diverse range of uses for flow meters. They have applications for individuals, a common one being to help people with asthma. A peak flow meter measures the lung capacity when someone exhales. This can help to predict an imminent asthma attack.

Other than that, flow meters are used in many industries, like the food processing industry, water management, semi conductor fabrication and many others. This article will give a brief overview of how flow meters work.

There are a wide variety of types of flow meters. They are generally classified by what they do or how they operate. For instance, a mass flow meter is a general classification of flow meter that determines the flow rate of a medium in terms of mass even though the operating principles for each meter may be different.

One example of a principle governing the name of a meter is the Coriolis flow meter. It uses the Coriolis effect to determine the mass of a fluid passing through two vibrating tubes or pipes. The idea being that by understanding the change in the characteristics of the wave patterns in the vibrating tubes, you can correlate the flow rate of the substance passing through.

Ultrasonic and Doppler shift flow meters also use the changes caused to sound waves to correlate a rate of flow for the medium passing through the meter.

In the case of the ultrasonic flow meter, two transmitters of ultrasonic sound waves are placed at the ends of a pipe where the measure is to take place. Each transmitter sends a pulse of sound.

Receivers at opposite ends of the pipe record the sound waves. One pulse of ultrasonic wave is sent off in the direction of the flow while the other is in the opposite direction.

If various constants are known about the metal of the pipe and the liquid or gas passing through the pipe, a rate of flow can be derived from the time it takes each sound wave to reach the receiver.

Doppler shift flow meters also use waves to determine the flow rate. They work on the principle that a sound wave that bounces off a moving particle in the medium has it’s frequency and amplitude changed. By determining the change in these dimensions, the flow rate of the medium can be determined.

A more traditional type of flow meter is the variable area flow meter that uses a float in a calibrated tube. When a substance passes through the tube, the float is displaced by the flow.

The float indicates a measurement on the calibrated tube. This is a correlation of the flow rate of the substance that has just passed through the tube. An example of such a device is the peak flow meter that is used to measure lung capacity. Peak flow meters help people with asthma determine if they are likely to have an asthma attack.

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Learn more about how do flow meters work and information on fuel flow meters at http://www.flowmetermatters.com.