Ultrahelivootajuri ultraheliheli kandub voolava keskkonnaga/vedelikuga torusse ja peegeldunud ultrahelilaine omab veidi erinevat sagedust, mis on otseses seoses voolava keskkonna/vedeliku vookiirusega.
Ultrasonic sound of the ultrasonic flow sensor is transmitted into a pipe with flowing liquids, and the discontinuities reflect the ultrasonic wave with a slightly different frequency that is directly proportional to the rate of flow of the liquid.
