Air Flow Meter/Sensor: Description and Operation
DescriptionThe type of air flow sensor is a hot film and composed of a hot film sensor, housing, metering duct (power transistor, sensor element).
Mass air flow rate is measured by detection of heat transfer from a hot film probe and the change of the mass air flow rate causes change in the amount of heat being transferred from the hot wire probe surface to the air flow. This results in the change of the temperature of the hot wire probe and in the change of resistance.