Abstract: A measuring tube for guiding a fluid for a flow meter device according to the vortex measuring principle, wherein the measuring tube has an inflow-side opening in an inflow-side end face and an outflow-side opening in an outflow-side end face, between which the measuring tube extends in the axial direction includes: a bluff body which is arranged in the measuring tube, wherein the bluff body functions to bring about a Kármán vortex street with a flow-rate-dependent vortex frequency when a fluid flows through the measuring tube; at least one vortex detector for detecting vortexes of the vortex street and for providing vortex-dependent signals; and a control valve between the vortex detector and the outflow-side end face and axially spaced apart from the vortex detector, which annularly constricts the flow cross-section of the measuring tube.

Abstract: The invention relates to: a measuring tube (10) for guiding a fluid for a flow meter device (1) according to the vortex measuring principle, wherein the measuring tube has an inflow-side opening in an inflow-side end face and an outflow-side opening in an outflow-side end face, between which the measuring tube extends in the axial direction; a bluff body (15) which is arranged in the measuring tube (10), wherein the bluff body functions to bring about a Kármán vortex street with a flow-rate-dependent vortex frequency when a fluid flows through the measuring tube; and at least one vortex detector (16) for detecting vortexes of the vortex street and for providing vortex-dependent signals; characterized in that the measuring tube (10) has a control valve (14), between the vortex detector (16) and the outflow-side end face and axially spaced apart from the vortex detector, which annularly constricts the flow cross-section of the measuring tube (10).