Flowmetering of Shear-Thinning Non-Newtonian Liquids (Keynote)

This paper describes the results of an investigation into the performance of Coriolis, Electromagnetic, and clamp-on single-beam Ultrasonic flowmeters operating with non-Newtonian liquids. The flowmeters have been tested on Newtonian liquids (water and a glycerine/water solution) and non-Newtonian liquids (various polymer solutions and a synthetic clay) with flow rates that span the laminar and turbulent regions. It has been shown that the Coriolis flowmeter operates within the manufacturer’s specification with non-Newtonian liquids. The Electromagnetic flowmeter showed a slight deviation during transition, typically 1%. The Ultrasonic flowmeter showed very significant deviations during transition, typically 15%. It has been clearly demonstrated that flowmeters which are sensitive to flow velocity profile are particularly unsuitable for use with non-Newtonian liquids. Not only do non-Newtonian liquids have different flow velocity profiles to Newtonian liquids, they also have different criteria for laminar/turbulent transition.