Vortex Flowmeter Technical Description The is used for experiments on various methods of measuring volumetric and mass flow rates. 2 continuous and 2 intermittent methods are introduced. The continuous methods include a vortex flow meter and a variable-area flow meter. In the vortex flow meter an oscillating vortex is produced, the frequency of the oscillation is proportional to the flow rate. The vortex is made visible using ink. The gravimetric measurement using precision scales can be used as a comparison measurement. The flow rate can be finely adjusted using a manual valve. A comparison of the measurements using the different methods is possible. The water supply is provided either from the laboratory (closed water circuit).