By applying an alternating voltage, the piezoelectric expands and contracts periodically and emits a sound wave corresponding to the excitation frequency. This sound wave is sent out as a pulsating ultrasonic beam from an excitation transducer and is detected by a receiving transducer. The signal is evaluated electronically and output via various signal outputs (digital + analog).
Physical Principles of Ultrasonic Flow Sensors
There are different ways how ultrasonic signals can be utilized to calculate flow rates.
The SONOFLOW sensors work on the basis of the transit-time difference measurement method.
This method causes neither a pressure drop in the tube nor a risk of leaks. When appropriately calibrated, transit-time can work on almost all liquids, independent of viscosity, density, color and electromagnetic properties of fluids. Ions and particulate matter are not required to calculate the measurement.