Flow meter having a vortex body

摘要

Flow meters having vortex bodies, in which the triggering frequency of the self-forming Kármán vortex streets are detected as a measure of the flow velocity, use as measuring signal the forces generated by the triggered vortices and acting on the vortex body. The measuring pick-ups required for this purpose are sensitive and are necessarily contacted by the medium. In order to make possible a measurement of the triggering frequencies which is contactless and not influenced by disturbing frequencies, the vortex body (4) is positioned in the flowing medium transversely to the flow direction so as to be able to swing like a pendulum. An associated movement sensor (6, 7), which can be arranged on the exterior of the flow channel (1), detects without contact the swinging frequency as a velocity-dependent measuring signal. The measured value pick-up (6, 7) is not contacted by the medium. <IMAGE>