This package contains also the hardware accessory depicted below (also called sound speed unit). It allows to measure the sound speed in any kind of liquid when connected to the DOP3000 velocimeter. The measurement is based on a phase analysis of an echo generated by a mobile plate when this plate is moved over a known distance. Any transducers having a case diameter of 8mm or 12mm can be used. This enables the measurement of the sound speed at different ultrasonic frequencies.

The speed of sound in the investigated liquid has to be known for the DOP3000 to measure a calibrated velocity profile in it. The more precisely the speed of sound is known, the more accurate is the velocity value delivered by the DOP3000. For most common liquids, speed of sound at room temperature can easily be found in the literature (and even on our website). But some liquids are sometimes so specific, or used at such temperatures that a precise value of the speed of sound cannot be easily found. In such cases, it can be needed to measure the speed of sound in the specific user's conditions.