Use of nuclear magnetic resonance imaging as a viscometer for process monitoring

• Published in: Chemical engineering science Vol. 52; no. 13; pp. 2049 - 2057
• Main Authors: Arola, Darren F., Barrall, Geoffrey A., Powell, Robert L., McCarthy, Kathryn L., McCarthy, Michael J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.1997
• Subjects: Nuclear magnetic resonance imaging; shear rate; velocity; viscometer; viscosity; viscometer; shear rate; viscosity; velocity; Nuclear magnetic resonance imaging
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/S0009-2509(97)00033-X

Nuclear magnetic resonance imaging (NMRI or MRI) flow measurements and fundamental principles of capillary flow are combined to determine the shear viscosity of non-Newtonian fluids. Shear viscosity data are obtained over the shear rates inferred from the velocity profile measured using MRI. A single, 3 minute measurement consisting of a MRI-determined velocity profile (also referred to as a dynamic displacement profile or positiondisplacement correlation) and the corresponding pressure drop produces multiple shear viscosity-shear rate data points. This technique was applied to obtain shear viscosity-shear rate data for an aqueous carboxymethyl cellulose (CMC) solution. Good agreement is found between these data and those measured by conventional rotational rheometry. The potential applications of this MRI-based technique include on-line and in-line monitoring of the shear viscosity of single and multiphase non-Newtonian fluids that can be either opaque or transparent.