Measuring flow in vortex induction flowmeter - is by use of magnetic element varying magnetic field in hall effect device

摘要

Flow in a vortex induction flowmeter is measured utilising a vortex to cause vibrations at a frequency proportional to flow. A magnetic element is used to vary magnetic field in a Hall effect device to produce electrical signal for processing. A flowmeter comprises a tube (10) with large dia. collar (11) with chamfered edges (11A) to produce gentle flow. A obstacle (14) with rounded edges is placed across the tube to cause a nortex producing oscillation in a rear section (15) supported by hollow tube (16) containing permanent magnet (18) firmly fixed in the rear section. A hollow chamber (14) in the obstacle section contains a magnetically sensitive detector (19) the output of which is processed electrically.