Nondimensional scaling of magnetorheological rotary shear mode devices using the Mason number

Magnetorheological fluids (MRFs) exhibit rapidly adjustable viscosity in the presence of a magnetic field, and are increasingly used in adaptive shock absorbers for high speed impacts, corresponding to high fluid shear rates. However, the MRF properties are typically measured at very low (γ̇<1000 s−1) shear rates due to limited commercial rheometer capabilities. A custom high shear rate (γ̇>10,000 s−1) Searle cell magnetorheometer, along with a full scale rotary-vane magnetorheological energy absorber (γ̇>25,000 s−1) are employed to analyze MRF property scaling across shear rates using a nondimensional Mason number to generate an MRF master curve. Incorporating a Reynolds temperature correction factor, data from both experiments is shown to collapse to a single master curve, supporting the use of Mason number to correlate low- and high-shear rate characterization data.