Fig. 2

Presentation of all measuring points of the offline viscosity measurements for all experiments presented in this study in form of the modified Newton number (Ne′) dependent on the flask Reynolds number (Re). The Re number was calculated directly from the measured offline viscosity using Eq. 5 while the Ne′ number was calculated with Eq. 3 from the online determined power inputs measured at the same time points at which the samples for viscosity measurements were taken. The general Newton-Reynolds correlation (Eq. 4) of Büchs et al. [16] as well as the reduced Newton-Reynolds correlation established with the data in this work (Eq. 6) are also shown