화학공학소재연구정보센터
Journal of Rheology, Vol.41, No.6, 1365-1386, 1997
Nuclear-Magnetic-Resonance Visualization of Anomalous Flow in Cone-and-Plate Rheometry
We demonstrate the use of nuclear magnetic resonance (NMR) microscopy to image the velocity distribution for fluids sheared within the gaps (4 degrees and 7 degrees) of cone-and-plate rheometers. These measurements employ a specially constructed rheogoniometer, which fits within the NMR probe system. While the uniform shear rate assumption is verified in the case of simple Newtonian and non-Newtonian fluids, a range of anomalous behavior (apparent slip, shear banding, and fracture) is observed in other systems, including wormlike surfactants, semidilute solutions of 18 MDa polyacrylamide, and dispersed silica in silicone grease.