This measuring principle is based on the fact that turbulence forms downstream of obstacles in the flow, such as a bridge pier.

Inside each vortex flowmeter, a bluff body is therefore located in the middle of the pipe. As soon as the flow velocity reaches a certain value, vortices form behind this bluff body, are detached from the flow and transported downstream. The frequency of vortex shedding is directly proportional to mean flow velocity and thus to volume flow.