Development of an optimised magnetic field source for flowmeter applications. (April 2019)

• Record Type: Journal Article
• Authors: Sahu, Srikanta; Prajapati, Ashok; Kumar, Mritunjay; Bhattacharyay, Rajendraprasad
• Is Part Of: Flow measurement and instrumentation. Volume 66(2019)
• Page Start: 190
• Page End: 199
• Publication Date: 2019-04
• Subjects: Faraday' law -- Finite element method -- Liquid metal -- Magnetic flowmeter; Fluid dynamic measurements -- Periodicals; Flow meters -- Periodicals; Fluides, Dynamique des -- Mesure -- Périodiques; Débitmètres -- Périodiques; 681.2805
• DOI: 10.1016/j.flowmeasinst.2019.03.008
• Languages: English
• ISSNs: 0955-5986

Abstract

Abstract: Sensitivity of a magnetic flowmeter relies on many factors like magnetic field strength, gap between electrodes, material properties, magnet temperature etc. For a given measuring conditions, a strong magnetic field source can produce highest sensitivity for the flowmeter. An economic design of magnetic field source would be to produce the strongest magnetic field from a given amount of magnetic material. In this paper, various magnet configurations are analyzed using FEM and the flowmeter sensitivity using such magnet configurations are compared. It is observed that magnets arranged in a Halbach fashion produce the highest sensitivity for the flowmeter using a given amount of magnetic material. The major challenge for the development of such a magnetic field source is its fabrication from its constituent magnets, combatting their huge attractive/repulsive forces (∼2500 N for our case). Therefore, a specific mechanical tool has been designed for assembling the magnetic field source and a robust assembly technique has been devised using numerical computations. The designed magnetic field source produces a peak magnetic field of 0.78 T in the pole cross section of 50 mm × 50 mm. Highlights: An optimised magnetic field source has been developed for flowmeter applications. The magnetic field source can generate highest sensitivity for the flowmeter from a given weight of magnetic material. An assembly tool has been designed to the field source from its constituent magnets combating force ∼2500. Suitable assembly sequence has been devised using numerical computations.