The meniscus effect in viscosity determinations by the oscillating-cup method
Valentim Nunes, Maria Lourenço, Fernando Santos, Carlos Nieto de Castro
The object of this work was to evaluate the influence of the meniscus of liquid in the determination of viscosity by the oscillating-cup method. We measured the viscosity of water at 298.15 K with several heights of water inside the cup. Results obtained allow us to state that, if the cup is not almost completely filled, errors in the viscosity measurements can be larger than the uncertainty of the method. But, if the cup is filled up to 95% of the total height, the error in the viscosity determination can be smaller than 0.1%.