scholarly journals HUMORAL RHEOLOGY

1942 ◽  
Vol 26 (1) ◽  
pp. 49-64 ◽  
Author(s):  
Alfred L. Copley ◽  
Ludwig C. Krchma ◽  
Mary E. Whitney
Keyword(s):  
Apparent Viscosity ◽  
Specific Property ◽  
Age Hardening ◽  
Flow Properties ◽  
Specific Viscosity ◽  
Rolling Ball ◽  
Yield Value ◽  
The Relationship ◽  
Rolling Ball Viscometer ◽  
High Shearing

1. A modified falling ball viscometer (rolling ball viscometer) for blood and other humors is presented. It is capable of easily measuring flow properties at several stresses, as is required to define satisfactorily the properties of anomalous flow systems. At high shearing stresses, apparent specific viscosity values of 2.5 + are observed, corresponding to 2.2 ±0.2 reported as possible with the biological viscometer of Whittaker and Winton. 2. Previous references to the anomalous flow properties of blood were verified. It was demonstrated that these systems conform to the Bingham concept of anomalous flow. To define completely the flow properties of such systems it is necessary to make determinations at at least two shearing stresses, preferably more. Data are reported for the pseudoviscosity and yield value, the latter being possibly the most specific property of the three bloods studied. 3. Heparin in increasing amounts tended to decrease the apparent viscosity, pseudoviscosity, and yield value of blood. Similar increases of heparin also reduced the viscosites of the serum and plasma. 4. The ratio of the apparent viscosity of blood and its plasma was found to be reasonably constant as reported by Trevan. However, as the apparent viscosity is a function of the shearing stress, it is believed that the relationship for the calculations of corpuscular concentrations, such as the Whittaker and Winton modification of the Hatschek formula, is specific for the instrument and conditions of tests by which it was determined. 5. Heparinized blood was found to exhibit thixotropy, dilatancy, and age-hardening phenomena.

A Study of Flow of Plastics Through Pipes

1946 ◽  
Vol 13 (2) ◽  
pp. A101-A105
Author(s):  
R. C. Binder ◽  
J. E. Busher
Keyword(s):  
Experimental Data ◽  
Reynolds Number ◽  
Friction Coefficient ◽  
Laminar Flow ◽  
Turbulent Flow ◽  
Dynamic Viscosity ◽  
Apparent Viscosity ◽  
Turbulent Viscosity ◽  
Yield Value

Abstract The pipe friction coefficient for true fluids is usually expressed as a function of Reynolds number. This method of organizing data has been extended to tests on the flow of different suspensions which behaved as ideal plastics in the laminar-flow range and as true fluids in the turbulent-flow range. In the laminar-flow range, Reynolds number below about 2100, the denominator in Reynolds number is taken as the apparent viscosity. The apparent viscosity can be determined from the yield value and the coefficient of rigidity. In the turbulent-flow range, the denominator in Reynolds number is an equivalent or turbulent viscosity equal to the dynamic viscosity of a true fluid having the same friction coefficient, velocity, diameter, and density as that of the plastic. The various experimental data on plastics correlate well with this extension of the method for true fluids.

Effects of Flow Properties of Lithium Soap Greases on Bearing Torque

2019 ◽  
Vol 823 ◽  
pp. 123-127
Author(s):  
Norifumi Miyanaga ◽  
Mitsumi Nihei ◽  
Jun Tomioka
Keyword(s):  
Apparent Viscosity ◽  
Small Amplitude ◽  
Shear Stresses ◽  
Flow Properties ◽  
Small Amplitude Oscillatory Shear ◽  
Small Ball ◽  
Shear Rates ◽  
Lithium Soap ◽  
Viscoelastic Behaviors ◽  
Plate Type

This study describes the influence of flow properties of lithium soap greases on torque of small ball bearings. Three types of greases with different worked penetration were tested in this study. Their rheological properties are revealed by a cone plate type rheometer. Shear stresses under various shear rates are fitted with the Herschel-Bulkley equation. In addition, viscoelastic behaviors of the greases are measured by small amplitude oscillatory shear. The crossover stress that means the shear stress at G’=G” is obtained for the greases. Then, the bearing torque when three types of greases are used as a lubricant is measured. As the results, the grease with higher crossover stress shows the lower bearing torque regardless of that it has larger apparent viscosity. On the other hand, the grease with lower crossover stress shows the higher bearing torque regardless of that it has lower apparent viscosity. These results imply that the channeling state appears in the grease with higher crossover stress while the churning state appears in the grease with lower crossover stress.

Rolling Ball Viscometer

1943 ◽  
Vol 15 (3) ◽  
pp. 212-218 ◽  
Author(s):  
Robert Hubbard ◽  
George Brown
Keyword(s):  
Rolling Ball ◽  
Rolling Ball Viscometer

Influence of fibrinogen on flow properties of erythrocyte suspensions

1964 ◽  
Vol 207 (5) ◽  
pp. 1035-1040 ◽  
Author(s):  
Roe E. Wells ◽  
Thomas H. Gawronski ◽  
Paul J. Cox ◽  
Richard D. Perera
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Cell Aggregation ◽  
Cell Suspensions ◽  
Fibrinogen Concentration ◽  
Sedimentation Rates ◽  
Cell Aggregates ◽  
Red Cell ◽  
Flow Properties ◽  
Yield Value

The influence of fibrinogen on the flow properties of red cell suspensions (hematocrit 41) was studied by viscometry at low rates of shear (0.1–20 sec–1). These findings were correlated with sedimentation rates and photomicrographical studies of cell aggregation. Fibrinogen concentration was varied from 0.3 to 2.0 g/100 ml. The viscosity of the pure solutions of fibrinogen was independent of shear rate, ranging from 0.87 to 1.7 centipoise (cp) at 37 C. The viscosity of the cell suspensions at 10 sec–1 varied from 4.3 cp in 0.3 g/100 ml fibrinogen to 14 cp in 2 g/100 ml fibrinogen. All suspensions were markedly dependent on shear rate, viscosity increasing in exponential-like fashion as shear rate decreased. Extrapolation of plots of shear stress1/2 versus shear rate1/2 revealed the suspensions to sustain a finite stress without deformation or flow, the "yield value" increasing as fibrinogen concentration increased. Photomicrographs of dilute cell suspensions revealed the formation of cell aggregates and rouleaux, increasing in size and descent velocity as fibrinogen concentration increased.

scholarly journals Rheological and sensory characteristics of yoghurt-modified mayonnaise

2008 ◽  
Vol 26 (No. 3) ◽  
pp. 190-198 ◽  
Author(s):  
P. Štern ◽  
J. pokorný ◽  
A. Šedivá ◽  
Z. Panovská
Keyword(s):  
Apparent Viscosity ◽  
International Standards ◽  
Sensory Characteristics ◽  
Rheological Measurements ◽  
Significant Relationships ◽  
Yield Value ◽  
Rapid Prediction ◽  
Static Yield ◽  
Sensory Parameters ◽  
Increasing Temperature

Rheological and textural characteristics were studied in a set of 11 samples of yoghurt-modified mayonnaise at 15, 20, and 25°C. The rheometer Rheostress 300 was used to determine the static yield value, apparent viscosity, thixotropy, and elasticity. The sensory texture and flavour profiles were developed and determined in agreement with the respective international standards, using a group of selected and trained assessors. The yield value and apparent viscosity substantially decreased with increasing temperature, but thixotropy and sensory characteristics were not significantly affected by temperature. Linear and semilogarithmic relations were observed between the analytical parameters, but more complex relations, showing a maximum or a minimum, were found in some cases. Thixotropy was related to most of the sensory parameters, viscosity was related to spreadability, and significant relationships existed between the texture acceptability and the flavour acceptability. Rheological measurements were thus useful for a rapid prediction of the sensory properties of yoghurt-modified mayonnaises, but could not be used to replace any textural analysis.

Apparent Viscosity and Rheological Behavior of Aluminum-Alloy Slurry Containing Nano-Sized SiC Particles

2019 ◽  
Vol 285 ◽  
pp. 391-397
Author(s):  
Kang Lu ◽  
Shu Sen Wu ◽  
Shu Lin Lü ◽  
Chong Lin
Keyword(s):  
Aluminum Alloy ◽  
Rheological Behavior ◽  
Apparent Viscosity ◽  
Mass Fraction ◽  
Matrix Alloy ◽  
Rotating Cylinder ◽  
Viscous Force ◽  
Semi Solid ◽  
The Relationship ◽  
Cylinder Viscometer

The apparent viscosity and rheological behavior of nanoSiCP/Al-5Cu composites were studied by using a high temperature coaxial rotating cylinder viscometer. The results show that mass fraction of nanoSiCP is an important factor for apparent viscosity of the nanoSiCP/Al-5Cu composites, and there is a great enhancement of apparent viscosity of the slurry with the increase of nanoSiCp content. It can attribute to the viscous force between nanoSiCp and matrix alloy melt above the liquidus. The increased amplitude of apparent viscosity in semi-solid state is far less than those in liquid state with the increase of mass fraction of nanoSiCp. The apparent viscosities of the composites reinforced with 0.5%, 1%, 1.5% and 2% nanoSiCp at 700°C were 24.78%, 95.25%, 160.29% and 228.62% higher than that of Al-5Cu alloy, respectively. Besides, the rheological model of nanoSiCP/Al-5Cu composites was established based on the fitting curve, which can precisely describe the relationship between the apparent viscosity of nanocomposites slurry and nanoSiCp mass fraction.

Investigation on the Rheological Behavior of PA1010/POE/OMMT Nanocomposites

2012 ◽  
Vol 482-484 ◽  
pp. 2582-2586
Author(s):  
Yan Fei Zhang ◽  
Ying Chun Li ◽  
Guo Sheng Hu
Keyword(s):  
Activation Energy ◽  
Rheological Behavior ◽  
Apparent Viscosity ◽  
Experimental Results ◽  
Shearing Stress ◽  
Pseudoplastic Fluid ◽  
High Shearing

The rheological behavior of PA1010/POE/OMMT nanocomposites was studied by using XLY-Ⅱ rheometer. The curves of lgτω～lgγ’ω, lgηa～lgγ’ω, lgηa～1/T were obtained. The experimental results showed that PA1010/POE/OMMT nanocomposites were pseudoplastic fluid. The apparent viscosity of the blends reduced with the increase of the shearing stress．Compared with PA1010/POE blends, the addition of OMMT increased the apparent viscosity. The viscous activation energy of PA1010/POE/OMMT blends declined as the increase of shearing stress, which indicated that the PA1010/POE/OMMT blends could be processed over a wide temperature at a high shearing stress.

THE EFFECT OF PRECIPITATION CONDITIONS ON THE FLOW PROPERTIES OF SILICA DISPERSIONS

1955 ◽  
Vol 33 (2) ◽  
pp. 391-395
Author(s):  
A. F. Sirianni ◽  
I. E. Puddington
Keyword(s):  
Sodium Silicate ◽  
Marked Effect ◽  
Liquid Interface ◽  
Liquid Hydrocarbons ◽  
Flow Properties ◽  
Yield Value ◽  
Solid Liquid Interface ◽  
Solid Liquid

The pH of the solutions in which silica is precipitated from sodium silicate has a marked effect on the flow properties of pastes prepared by subsequently dispersing the silica in liquid hydrocarbons. The yield value of this non-Newtonian suspension exhibits a pronounced maximum when silica precipitated at about pH 5 is used. An explanation based on the properties of the solid–liquid interface is proposed.

A VISCOMETRIC METHOD FOR THE ESTIMATION OF MILK CELL COUNT

1970 ◽  
Vol 33 (8) ◽  
pp. 351-354
Author(s):  
W. G. Whittlestone ◽  
L. R. Fell ◽  
H. De Langen
Keyword(s):  
Cell Count ◽  
Correlation Coefficient ◽  
Coefficient Of Variation ◽  
Rolling Ball ◽  
Simple Apparatus ◽  
Microscopic Count ◽  
Rolling Ball Viscometer

The use of a rolling ball viscometer to estimate the cell count of milk treated with California Mastitis Reagent is described. The method compares favorably with the direct microscopic count and requires relatively simple apparatus and unskilled operators. A correlation coefficient for mean count and log viscometer time of 0.93 with a coefficient of variation of 8.1% were obtained. The repeatability of viscometer readings was 0.97.

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