Rosemount Vortex flow meters, often called vortex shedding flow meters, provide accurate and reliable flow measurement for a wide range of flow applications. DP flow meters use an obstruction in the flow stream to create downstream vortices. As these vortices are shed from the obstruction, they create alternating low and high-pressure zones that oscillate at particular frequencies directly proportional to the velocity of the fluid. The flow rate can then be calculated from the fluid velocity. Vortex slow meters are ideal for measuring the flow rate of liquids, gases, and steam and remain unaffected by changes in pressure, temperature and viscosity. Without moving parts, vortex meters are easy to install and require little maintenance. Since the measuring signal does not drift, vortex meters can operate its entire service life without recalibration.