was highly beneficial to reducing the AF/PV ratio because it reduced mixing within the pipe and reduced heat transfer between the water and the pipe wall.
That reportedly imposes different requirements for residence time, shear flow
, and thermal balance.
This machine is designed to maximize heat transfer, to impart controlled squeeze and shear flow
mixing, and to eliminate variability that can occur due to changes in the plant air supply, typically creating variability in the mixing process where pneumatic hoppers were used.
Structural information on aggregated particle systems has been obtained using confocal laser scanning microscopy and transmission electron microscopy (casein gels and heat-set b-lactoglobulin gels); from observations of adsorbed layers in shear flow
(polystyrene particles); and by diffusing wave spectroscopy (renneted skim milk particles).
CHEN: I'm wondering why the experiments do not start with a constant shear flow
which is then changed.
Prof Steffe has ensured that emphasis is placed on problems that are most commonly encountered by food process engineers, like steady shear flow
This is because sustained shear flow
is easy to build up using relatively simple geometries compared to elongational flow field, also present at a different extent and whose contribution depends on the type of mixer.
Although many industry processes involve very high shear flow
, the viscosity of liquids is typically not measured at the shear rates experienced in these processes.
Two different types of flow occur in parallel (figure 3) in the mixing operation--elongation flow, shown by the blue arrows in the top part, and shear flow
, shown in the bottom part.
Rotational shear flow
breaks up the droplets of the dispersed phase, which isn't always achieved with high-viscosity fluids in conventional mixers.
Unlike typical existing mixers, the CRD mixer does not rely mostly on shear flow
whereby the plastic receives only one high-stress exposure.