An airflow sensor is a device used to measure the volume of air flowing through a duct, pipe, or other enclosed space. Airflow sensors are used in a variety of applications, including heating, ventilation, and air conditioning (HVAC) systems, engine management systems, and industrial process control systems.
Airflow sensors can be classified into two main types: thermal and mechanical. Thermal airflow sensors measure the temperature difference between a heated element and the surrounding air. As the air flow rate increases, the temperature difference decreases, and vice versa. Mechanical airflow sensors measure the deflection of a diaphragm or other mechanical element caused by the air flow.