scholarly journals Transient Viscosity of Polymer Solutions after Stepwise Change of Shear Rates

1986 ◽  
Vol 14 (3) ◽  
pp. 132-135 ◽  
Author(s):  
Yoshiaki TAKAHASHI ◽  
Yoshinobu ISONO ◽  
Ichiro NODA ◽  
Mitsuru NAGASAWA
Keyword(s):  
Polymer Solutions ◽  
Shear Rates ◽  
Stepwise Change ◽  
Transient Viscosity

Nonnewtonian Flow of Poly(Dimethyl Siloxane)

1967 ◽  
Vol 40 (5) ◽  
pp. 1483-1491
Author(s):  
Yoshio Ito
Keyword(s):  
Shear Rate ◽  
Polymer Solutions ◽  
Flow Behavior ◽  
Degree Of Polymerization ◽  
High Shear ◽  
Newtonian Viscosity ◽  
Shear Rates ◽  
Molecular Weights ◽  
Dimethyl Siloxane ◽  
Wide Range

Abstract Nonnewtonian flow of poly(dimethyl siloxanes) of various molecular weights has been studied with a short capillary viscosimeter. The experiment covered a wide range of shear rate, from 10−1 to 3×106sec−1. Results were as follows: (1) Flow behavior of the sample changes with the degree of polymerization. For siloxanes with degrees of polymerization less than 1.55×102, flow of the fluid is newtonian throughout the whole range of shear rates; for siloxanes with degrees of polymerization from 3.22×102 to 2.63×103, flow is nonnewtonian at moderate shear rates; it again becomes newtonian at high shear rates. With degrees of polymerization more than 3.31×103, the spiral flow rises to a high shear rate. (2) Plow behavior of the samples is expressed by modifying Shishido's equation proposed for nonnewtonian polymer solutions. (3) When the observed flow curve contains its inflection point, the upper newtonian viscosity can be estimated by a new method proposed here. (4) The relations among the end correction of capillary, the pressure loss, and the shear stress proposed by Shishido for polymer solutions are applicable to poly(dimethy! siloxane) also.

Mobility Control With Polymer Solutions

1967 ◽  
Vol 7 (02) ◽  
pp. 161-173 ◽  
Author(s):  
W.B. Gogarty
Keyword(s):  
Polymer Solution ◽  
Polymer Solutions ◽  
Control Mechanism ◽  
The United States ◽  
Mobility Control ◽  
High Shear ◽  
Polymer Flow ◽  
Shear Rates ◽  
High Shear Rates ◽  
Secondary Recovery

Abstract With the use of polymer solutions in secondary recovery operations, the need has developed to understand the mobility control mechanism. This study investigated mobility control by considering both permeability and rheological effects. Experiments used a high molecular weight, partially hydrolyzed polyacrylamide polymer. Flow studies took place in reservoir and Berea cores having zero oil saturation. Effective size of the polymer flow unit was inferred from Nuclepore filter tests. Clay studies indicated the particle size capable of decreasing the core permeability. Flushed permeabilities measured the approximate core permeabilities with flowing polymer solutions. These permeabilities were considerably lower than original values. With mobility data and the flushed permeability, maximum effective viscosities were determined for polymer solution flow in a core. Effective viscosities showed that rheological properties play an important part in mobility control with polymer solutions. The study showed that permeabilities decrease and stabilize with polymer flow. At the lower permeabilities, high shear rates exist in the cores. Because of the pseudoplastic character of the polymer solution, the high shear rates caused low effective viscosities. This condition pointed to the inefficient use of the potentially high viscosity of the polymer solution at low shear rates. Introduction In the oil industry, a great deal of interest is being shown in the use of polymer solutions for secondary recovery and a number of polymer floods are being performed in the United States. Some of these floods have become commercial while others have been reported as failures. A number of floods are still in progress and remain to be evaluated. With the advent of polymer flooding, the need developed to understand the mobility control mechanism in porous media.

Flows in Rotation Cylinder Filled With Polymer Solutions

2006 ◽  
Author(s):  
Jae Won Kim ◽  
JaeMin Hyun ◽  
Eun Young Ahn
Keyword(s):  
Apparent Viscosity ◽  
Polymer Solutions ◽  
Side Wall ◽  
Velocity Shear ◽  
Working Fluid ◽  
Shear Rates ◽  
Ctab Solution ◽  
Applied Shear Stress ◽  
Shear Front ◽  
Solid Walls

This investigation deals with the spin-up flows in a circular container of aspect ratio, 2.0. Shear front is generated in the transient spin-up process of the present flow system and it is propagating from the side wall to the central axis in a rotating container. Propagation of the shear front to the axis in a rotating container means the region behind the shear front acquires an angular momentum transfer from the solid walls. Propagating speed of the shear front depends on the apparent viscosity of polymer solution. Two kinds of polymer solutions are considered as a working fluid: one is CMC and the other is CTAB solution. CMC solution has larger apparent viscosity than that of water at the present applied shear stress, and CTAB shows varying apparent viscosities depending on the applied shear rates. Transient and spatial variations of the apparent viscosities of the present polymer solutions (CTAB and CMC) cause different propagating speeds of the shear front. In practice, CMC solution that has larger values of apparent viscosity than that of water always shows rapid approach to the steady state in comparison of the behavior of the flows with water. However, for the CTAB solution, the propagating speed of the shear front changes with the local magnitude of its apparent viscosity. Consequently, the prediction of Wedemeyer’s including viscosity in the propagating speed of the velocity shear front quantitatively agrees with the present experimental results.

Shear Dependence of Viscosity and Molecular Weight Transitions. A Study of Entanglement Effects

1967 ◽  
Vol 40 (2) ◽  
pp. 522-531
Author(s):  
Suresh N. Chinai ◽  
William C. Schneider
Keyword(s):  
Molecular Weight ◽  
Shear Rate ◽  
Polymer Solutions ◽  
Shear Rates ◽  
Molecular Weights ◽  
Critical Molecular Weight

Abstract Flow of concentrated polymer solutions covering molecular weights up to 150,000 was examined at shear rates up to 200,000 sec−1. The viscosity, molecular weight, and shear rate results of previous workers recognizing only single critical molecular weight M*, above which ordinary Bueche entanglements dominated the flow, were compared with our findings in which two distinct critical molecular weights, upper M* and lower M** exist. These results are compared with the theory, and new interpretations are presented.

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