The vortex shedding flowmeter first emerged 25 to 30 years ago and has steadily grown in acceptance since then to be a major flow measurement technique. Its appeal is due, in part, to the fact that it has no moving parts yet produces a frequency output that varies linearly with flowrate over a wide range of Reynold’s numbers. The vortex meter has a very simple construction, provides accuracy (1% or better) comparable to higher price and/or more maintenance intensive techniques and works equally well on liquids and gases. In addition it is powered primarily by the fluid and lends itself more readily than other linear flow devices to two -wire operation. Comparing the vortex shedding flowmeter to an orifice plate the former has higher accuracy and rangeability, does not require complex pressure impulse lines, is less sensitive to wear and, for volumetric flow measurement, does not require the need to compensate for fluid density.
FOXBORO (2010) Vortex Shedding Tutorial