Ultrasonic flow meters are inferential meters that use ultrasonic technology to measure the velocity of an acoustically conductive liquid moving through it. There are two types of ultrasonic flow meter technologies, including Doppler and transit time. In addition to inline and open channel models, ultrasonic meters are available as clamp-on solutions when contact with the measured fluid is not possible. 

Measuring Principle

Ultrasonic meters measure the velocity of a fluid flowing through a pipe in one of two ways: transit time or Doppler technology. Transit time technology measures the time differential between signals sent upstream and downstream. The differential is directly proportional to the velocity of the water. Doppler technology measures the difference in sound wave frequency reflected off gas bubbles or particles in the flow stream.