The objective of this work was to assess the impact of filamentous bacteria on the settling velocity and rheological behaviour of activated sludge. We then identified the relevant settling and rheological model parameters to account for the impact of filamentous bulking on the prediction of sludge mixing and transport in secondary settling tanks by a computational fluid dynamics (CFD) model. We...

We use stroboscopic video microscopy to study the motion of a sheared fluid-gel interface. Mechanical noise plays a role analogous to temperature, but with a low-frequency breakdown of linear response consistent with an underlying instability. We relate the fast motion of the interface to the rheological properties of the gel, laying the foundation for a non-Brownian optical microrheology.

BACKGROUND AND METHODS It is important to ensure that blood flow is modelled accurately in numerical studies of arteries featuring drug-eluting stents due to the significant proportion of drug transport from the stent into the arterial wall which is flow-mediated. Modelling blood is complicated, however, by variations in blood rheological behaviour between individuals, blood's complex near-wall...

© Appl. Rheol. 15 (2005) 90-97 Abstract: There is often a need to perform rheological tests on dilute polymeric liquids at a time long after their initial preparation, for example if a more sensitive or novel method of measuring a material property (such as uniaxial/biaxial extensional viscosity or second normal-stress differences) becomes available. An inexpensive method of storing such fluids...

The rheological characteristics of digested sludge are severely temperature dependent. An effect of temperature on rheological properties of digested sludge is partially irreversible. In this paper, the effects of temperature change and thermal history on viscosity of digested sludge were studied using a stress-controlled rheometer which was connected to a temperature controlled water bath. Dig...