The vortex flow meter is used for measuring the flow velocity of gases and liquids in pipelines flowing full. Vortex flow meters detect and convert pressure changes into electrical signals. Pressure changes are caused when a shedder bar creates Karman vortices. When a shedder bar is placed in a fluid, Karman vortices are generated on the downstream side. The vortex frequency is proportional to the flow velocity, and corresponds to a specific range of Reynolds numbers.