Ultrasonic Flow Meters
Ultrasonic flow meters are inferential meters that uses ultrasonic technology to measure the velocity of an acoustically conductive liquid moving through it. There are two types of ultrasonic flow meter technologies: Doppler shift and transit-time.
Transit-time measures the time differential between signals sent upstream and downstream. The differential is directly proportional to the velocity of the water. Transit-time meters are best used for measuring the flow of clean liquids and, as a result, are the most popular type of ultrasonic meter. Doppler shift measures the difference in frequency of the sound wave reflected off gas bubbles or particles in the flow stream and is suitable for aerated or dirty liquids.