TY - GEN
T1 - An experimental investigation into the off-state viscosity of MR fluids
AU - Gudmundsson, K. H.
AU - Jonsdottir, F.
AU - Thorsteinsson, F.
AU - Gutfleisch, O.
PY - 2011
Y1 - 2011
N2 - This study investigates the off-state rheological characteristics of magnetorheological (MR) fluids. Various carbonyl iron powder grades are tested, both micron- and nano-sized. The study considers both monodisperse and bidisperse MR fluid samples. The bidisperse MR fluids are both micron-sized only compositions and mixed micron- and nano-sized compositions. All fluid compositions employ a novel perfluorinated polyether (PFPE) oil as a base fluid. This base fluid is introduced and its qualities discussed. An off-state experimental investigation is conducted, for shear-rates from 0 to 200 s -1. All samples exhibit the well known shear-thinning property of MR fluids but with varying proportions. The off-state viscosity is of importance in a particular application, in an MR prosthetic knee. It determines how fast the knee joint can rotate in the absence of a magnetic field. A prominent MR fluid composition is selected for the proposed application which aims to maximize to rotational speed of the MR knee joint in the absence of a magnetic field.
AB - This study investigates the off-state rheological characteristics of magnetorheological (MR) fluids. Various carbonyl iron powder grades are tested, both micron- and nano-sized. The study considers both monodisperse and bidisperse MR fluid samples. The bidisperse MR fluids are both micron-sized only compositions and mixed micron- and nano-sized compositions. All fluid compositions employ a novel perfluorinated polyether (PFPE) oil as a base fluid. This base fluid is introduced and its qualities discussed. An off-state experimental investigation is conducted, for shear-rates from 0 to 200 s -1. All samples exhibit the well known shear-thinning property of MR fluids but with varying proportions. The off-state viscosity is of importance in a particular application, in an MR prosthetic knee. It determines how fast the knee joint can rotate in the absence of a magnetic field. A prominent MR fluid composition is selected for the proposed application which aims to maximize to rotational speed of the MR knee joint in the absence of a magnetic field.
UR - http://www.scopus.com/inward/record.url?scp=84865624785&partnerID=8YFLogxK
U2 - 10.1142/9789814340236_0093
DO - 10.1142/9789814340236_0093
M3 - Conference contribution
AN - SCOPUS:84865624785
SN - 9814340227
SN - 9789814340229
T3 - Electro-Rheological Fluids and Magneto-Rheological Suspensions - Proceedings of the 12th International Conference
SP - 679
EP - 685
BT - Electro-Rheological Fluids and Magneto-Rheological Suspensions - Proceedings of the 12th International Conference
PB - World Scientific Publishing Co. Pte Ltd
T2 - 12th International Conference on Electrorheological Fluids and Magnetorheological Suspensions, ERMR 2010
Y2 - 16 August 2010 through 20 August 2010
ER -