In viscometry, shear stress and rate are estimated under the assumption that there is no slip between fluid and wall in contact. Rotational viscometry is usually accompanied by high test range of shear rates and suspected to avoid wall slip. This phenomenon was reflected by the experimental result that viscosities measured with different sizes of rotor were not consistent even among the same specimens. Squeezing viscometry is run at relatively low shear rates. The slip in rotational viscometry was determined compared with that of the squeezing viscometry, which resulted in a higher possibility of slip.
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