| An emitter (1) sends ultrasonic waves into the flowing medium. These waves hit on particles (2) which move in the flowing direction and are reflected. Such particles may be e.g. sediment, contamination or air bubbles in the liquid. The receiver detects the shift in the reflected waves caused by the forward movement of the reflecting particles. |
The difference of frequency between the emitted and the received waves is the gauge for the motion speed of the particles and consequently the measurement of the flow speed.
Application examples for the ultrasonic flow monitoring devices from Anderson-Negele