Vortex Flow Meters
Vortex Flow Meters are used for measuring the flow velocity of gases and liquids in pipelines flowing full. The measuring principle is based on the development of a Karman vortex shedding street in the wake of a body built into the pipeline. The periodic shedding of eddies occurs first from one side and then from the other side of a bluff body (vortex-shedding body) installed perpendicular to the pipe axis. Vortex shedding generates a so-called “Karman vortex street” with alternating pressure conditions whose frequency is proportional to the flow velocity. In some cases, Vortex Flow Meters require the use of straightening vanes or straight upstream piping to eliminate distorted flow patterns and swirl. Low flowrates present a problem for Vortex Flow Meters, because they generate vortices irregularly under low flow conditions. The accuracy of vortex meters is from medium to high, depending on model and manufacturer. In addition to liquid and gas flow measurement, vortex flowmeters are widely used to measure steam flow.
