The Doppler effect, discovered in 1842 by Christian Doppler, is familiar to most of us; stationary observers of waves such as sound waves will see wavelengths that depend on the relative motion ...

Ultrasonic flow meters are non-invasive devices that use acoustic vibrations to determine the flow rate of a liquid. There are two types of ultrasonic flow meters – Doppler and transit time. Both ...

These are the type of flow meters that measure the velocity of liquid or gas by using the principle of ultrasound or sounds waves. Fast digital signal processors and sophisticated signal analysis ...

Panasonic Corporation has developed an ultrasonic gas flow and concentration sensor for hydrogen that enables the real-time simultaneous measurement of the flow rate and concentration of hydrogen ...