A brief history of ultrasonic flow meters Date: 23/01/20 | In: Water Meters You may be given to thinking that ultrasonic flow meters are a relatively recent invention. Not so. The history of ultrasonic flow meters spans some six decades. It first began in Japan with Japanese physicist, Shiego Satomura. Doppler technology In 1959, Satomura created an ultrasonic flowmeter that used doppler technology. It was specifically designed to deliver blood flow analysis. It wasn’t until four years later, in 1963, that the earliest ultrasonic flow meters for industrial applications made their appearance. Over the next 20 years, a variety of ultrasonic flow meters were developed. This included the launch of a clamp-on flow meter, but most products were based around the doppler method. The implementation of ultrasonic flow meters was quite complex to comprehend. They were often misapplied which didn’t do much for their reputation with end users! Time-of-flight technology The development of time-of-flight ultrasonic technology in the 1990s was a turning point. It ensured a widespread take up of time-of-flight flow meters for use within both the waste and clean water industries. Technology continues to progress and the ultrasonic flow meter is constantly evolving. This is largely thanks to the development of sophisticated sensors, microprocessors and lithium batteries amongst other technical advancements. What are the different types of ultrasonic flow meter? There are four different types of ultrasonic flow meter available on the market today. These are: Doppler velocity – uses reflected ultrasonic sound to measure the velocity of fluid Radar – uses microwave technology to transmit short pulses that reflect off a moving surface back to the sensor to determine velocity Ultrasonic clamp on – ideal for applications where it is difficult or impossible to access the pipe or process line Ultrasonic level – ideal for ascertaining the level of liquid within both open and closed channels We’ll explore and discuss the specific advantages and disadvantages of each of these ultrasonic flow meters in separate blog posts.