An air flow meter is a device intended to measure the flow of air through a tube. A well known example is the air flow meter used in cars to determine how much air is entering the engine at any given time. This is used to regulate the firing of the engine and keep the car running smoothly. Air flow meters can be seen in a variety of settings and may include an assortment of features, depending on how they are supposed to be used.
The diameter of the tube is known and it is possible to indirectly determine the amount of air being moved through the tube with some mathematical calculations since the air flow meter provides information about the speed of the flow. Air flow meters are often attached to computer systems, and these systems can make calculations in addition to illuminating indicator lights as needed. When the meter clogs or malfunctions, a warning can light up, and warnings can also be issued when the air flow is higher or lower than it should be.
People can use an air flow meter to measure consumption, determining how much air goes through the tube over time. It is also possible to use these devices as part of a regulation system, where valves can be adjusted to increase or decrease air movement and the meter will provide real time feedback about what is happening inside the system so adjustments can be made as needed. An air flow meter may also be useful for experiments in the lab, as well as in other settings.
Common reasons for malfunction can include a clog in the intake valve, blockages or kinks in the line, or damage to the section of the meter designed to gauge flow. Many of these malfunctions will return errors as the readings from the air flow meter will no longer make sense. Minor problems may not be immediately identified, if they occur within the range of the air flow meter's expected tolerances.
Costs for these devices vary. Many are designed for specialty applications and cannot be replaced with generic versions, tending to make them more expensive. Others may have delicate fixtures for additional sensitivity, also causing a rise in price. It is important to make sure an air flow meter is the right size for an application, and to check the calibration to confirm accuracy before relying on the device for readings.