Flow behavior of erythrocytes. II. Particle motions in concentrated suspensions of ghost cells

1979 ◽  
Vol 71 (2) ◽  
pp. 383-407 ◽  
Author(s):  
H.L Goldsmith ◽  
J.C Marlow
1995 ◽  
Vol 39 (4) ◽  
pp. 795-795
Author(s):  
Yasufumi Otsubo

MRS Bulletin ◽  
1991 ◽  
Vol 16 (8) ◽  
pp. 32-37 ◽  
Author(s):  
Richard L. Hoffman

Numerous commercial products either exist as concentrated suspensions of small particles or involve the processing of concentrated suspensions during some stage of their manufacture. Examples include foods, adhesives and glues, ceramic dispersions, paints, and polymer dispersions such as polyvinyl chloride plastisols. As a result, it is important for engineers to understand the flow behavior of these systems and how the flow behavior affects the way these materials can be processed.For mahy years, progress in understanding the flow behavior of concentrated suspensions was slow compared to progress on dilute systems, partly because of how the study of suspensions evolved. Building on Einstein's classical work for dilute suspensions of rigid spheres, many authors attempted to modify his equations to predict the flow behavior of more concentrated suspensions, but the extension of Einstein's work met with limited success, because nonhydrodynamic interactions cari be just as important as the hydrodynamic interactions considered by Einstein, and multiple particle interactions quickly complicate the problem as the particle concentration increases.


2003 ◽  
Vol 2003 (0) ◽  
pp. 171
Author(s):  
Takatsune NARUMI ◽  
Yousuke OUMI ◽  
Shin SUGAWARA ◽  
Tomiichi HASEGAWA

Author(s):  
Harry L. Goldsmith

For the rheologist, blood is essentially a concentrated suspension of biconcave 8-μm diameter red cells (40–45% by volume) that circulates within the body in vessels from 25 mm down to 5 μm diameter. Here, we describe in vitro tracking of blood cells in a traveling microtube apparatus and in a counter-rotating micro cone-plate device at low Reynolds numbers, Re. Observations of the flow behavior of individual red cells reveal a marked and continuously changing deformation and interaction of the cells in shear, and this, together with their migration away from the vessel wall accounts for the low whole blood overall viscosity compared to other concentrated suspensions and emulsions. Red cells also strongly affect the flow behavior and interactions of platelets and of white cells, which although present at much lower concentrations (0.3% by volume), play key roles in thrombosis, hemostasis, and inflammation. Studies of the kinetics of the formation and break-up of receptor-ligand bonds between membranes of platelets and of white cells in shear flow revealed single bond strengths of 50 −200 nN. Such micro particle image velocimetry (μPIV) studies have recently been considerably refined and extended to in vivo vessels such as postcapillary venules. Using submicron fluorescent latex spheres, the existence of an impermeable and hydrodynamically effective surface layer (< 0.5 μm thick) extending out from the vessel endothelium has been confirmed. The lecture is illustrated by movies of blood flow in vitro and in vivo.


1975 ◽  
Vol 38 (6) ◽  
pp. 315-318 ◽  
Author(s):  
M. A. RAO ◽  
Y. D. HANG

The flow behavior of suspensions of yeast (Candida utilis) grown on sauerkraut waste was studied as a function of concentration at 25.8 C. Suspensions containing 5.8, 21.7, 22.6, 23.6, 24.7 and 27.0% dry solids behaved as Newtonian fluids. The viscosity of these suspensions increased exponentially with the concentration of dry solids. A 29.2% suspension showed time dependent shear-thinning behavior. The non-Newtonian characteristics of the suspension could be described by both the Power law and the Casson flow models.


2020 ◽  
Vol 117 (6) ◽  
pp. 619
Author(s):  
Rui Xu ◽  
Haitao Ling ◽  
Haijun Wang ◽  
Lizhong Chang ◽  
Shengtao Qiu

The transient multiphase flow behavior in a single-strand tundish during ladle change was studied using physical modeling. The water and silicon oil were employed to simulate the liquid steel and slag. The effect of the turbulence inhibitor on the slag entrainment and the steel exposure during ladle change were evaluated and discussed. The effect of the slag carry-over on the water-oil-air flow was also analyzed. For the original tundish, the top oil phase in the impact zone was continuously dragged into the tundish bath and opened during ladle change, forming an emulsification phenomenon. By decreasing the liquid velocities in the upper part of the impact zone, the turbulence inhibitor decreased considerably the amount of entrained slag and the steel exposure during ladle change, thereby eliminating the emulsification phenomenon. Furthermore, the use of the TI-2 effectively lowered the effect of the slag carry-over on the steel cleanliness by controlling the movement of slag droplets. The results from industrial trials indicated that the application of the TI-2 reduced considerably the number of linear inclusions caused by ladle change in hot-rolled strip coils.


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