The vortex flowmeter is a velocity-type flow measurement instrument designed based on the Kármán vortex street principle. It is widely used in the power industry for measuring the volumetric flow of liquids, gases, and steam. When fluid flows past a non-streamlined bluff body (such as a triangular prism) installed in the pipeline, regular vortices are alternately shed on the downstream side. The frequency of vortex shedding is directly proportional to the average flow velocity of the fluid. By detecting this frequency signal with a piezoelectric sensor, the volumetric flow rate of the fluid can be calculated. Vortex flowmeters feature a simple and robust structure with no moving mechanical parts. They offer notable advantages including low pressure loss, a wide measurement range, and high measurement accuracy. When measuring volumetric flow under operating conditions, the measurement is largely unaffected by variations in fluid density, pressure, temperature, or viscosity. Leveraging these strengths, the vortex flowmeter has become one of the core instruments in the power industry for measuring the flow of media such as boiler feedwater, main steam, superheated steam, condensate, and circulating water.
