Vane Air Flow Meter
The air flow meter has a simple structure and high reliability; however, the air intake resistance is large, the response is slow, and the volume is large.
Karman vortex air flowmeter The so-called Karman vortex refers to the vortexes that appear alternately in two columns of opposite directions of rotation generated downstream of the object when a cylindrical or triangular object is placed in the fluid.
Optical Karman Vortex Air Flow Meter
In the process of generating the Karman vortex, the air pressure on both sides of the vortex generator will change, and it will act on the metal foil through the guide hole to make it vibrate. When the light of the light-emitting diode shines on the vibrating metal foil, the phototransistor receives The reflected light on the metal foil is the light modulated by the vortex, and its output is demodulated to obtain a frequency signal representing the air flow.