The basic principle of the compressed air flow meter is […]
The basic principle of the compressed air flow meter is the Carmen vortex principle, that is, "the vortex separation frequency of the vortex is proportional to the flow velocity." The diameter of the transmitter body is basically the same as the nominal diameter of the instrument. The
A column of approximately isosceles triangle is inserted into the circulation body, the axis of the column is perpendicular to the flow direction of the measured medium, and the bottom faces the fluid.
When the measured compressed air flows through the cylinder, vortices are alternately generated on both sides of the cylinder, and the vortices are continuously generated and separated. Two staggered rows of vortices, or "vortex streets", are formed downstream of the cylinder.
Theoretical analysis and experiments have proved that the frequency of vortex separation is proportional to the flow velocity of the media on the column side. The vortices are staggered and separated, generating pulsating pressure in the wakes on both sides of the cylinder and behind the cylinder. The detection probe located inside (or behind) the cylinder is subjected to this tiny pulsating pressure, causing the The piezoelectric crystal element is subjected to an alternating stress and generates an alternating charge signal.