Rheological Characterization of Shear-Thinning Fluids with a Novel Viscosity Equation of a Tank-Tube Viscometer

Abstract A tank-tube viscometer and its novel viscosity equation were developed to determine flow characteristics of non-Newtonian fluids. The objective of this research is to test capabilities of the tank-tube viscometer and its novel non-Newtonian viscosity equation by characterizing rheological behaviors of well-known polyethylene oxide (MW 8000000) aqueous solutions as non-Newtonian fluids with 60-w% sucrose aqueous solution as a reference calibration fluid. Non-Newtonian characteristics of 0.3 - 0.7 wt% polyethylene oxide aqueous solutions were extensively investigated with the tank-tube viscometer and its non-Newtonian viscosity equation over the 294 - 306 K temperature range, and 55 - 784 s-1 shear rate range. The 60-w% sucrose aqueous solution was used as a reference/calibration fluid for the tank-tube viscometer. Dynamic viscosity values of 60 w% sucrose aqueous solution were determined with the calibrated tank-tube viscometer and its Newtonian viscosity equation at 299.15 K, and compared with the literature values.

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Numerical Simulations of a Centrifugal Pump With a Non-Newtonian Fluid: Influence on Performances of Different Rheological Modelling

Volume 2: Computational Fluid Dynamics ◽

10.1115/ajkfluids2019-4940 ◽

2019 ◽

Author(s):

Matteo Occari ◽

Valentina Mazzanti ◽

Francesco Mollica ◽

Enrico Munari ◽

Michele Pinelli ◽

...

Keyword(s):

Experimental Tests ◽

Newtonian Fluids ◽

Centrifugal Pumps ◽

Rheological Characterization ◽

Rate Range ◽

Shear Rates ◽

Rheological Modelling ◽

Pear Juice ◽

Dynamics Simulations

Abstract Centrifugal pumps change their performance with respect to water when processing non-Newtonian fluids. Many aspects about pumping of non-Newtonian fluids remain to be clarified due to complexity of the matter and the scarcity of investigations. In addition to experimental tests, in recent years some CFD fluid dynamics simulations have been realized to analyze the performance of centrifugal pumps with non-Newtonian fluids. Knowledge of rheology is required to correctly simulate the fluid inside the pump and predict the performance. The aim of this work is to emphasize the criticalities in the simulation of centrifugal pumps with non-Newtonian fluids, since, starting from the same rheological data, can be deduced different rheological laws, however reliable, that produce different effects on the simulations. In this paper, the performances of a model pump were measured experimentally with pear juice and accompanied by the rheological characterization of the fluid. Subsequently, the pump was simulated using five different rheology laws, all fitted to the same experimental rheogram, that differ from each other in predicting viscosity out of shear rate range experimentally measured. The pump performances were affected by the different rheology implemented. The simulations showed that the shear rates developed inside the pump are much higher than those measured with the rheometer. Consequently is necessary to achieve higher shear rates in the experimental rheogram to make sure to correctly model the rheology for shear rates values typically present in the pump.

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On the Aqueous Solution Behavior of C-Substituted 3,1,2-Ruthenadicarbadodecaboranes

Inorganics ◽

10.3390/inorganics7070091 ◽

2019 ◽

Vol 7 (7) ◽

pp. 91 ◽

Cited By ~ 3

Author(s):

Marta Gozzi ◽

Benedikt Schwarze ◽

Peter Coburger ◽

Evamarie Hey-Hawkins

Keyword(s):

Aqueous Solution ◽

Aqueous Solutions ◽

Self Assembly ◽

Self Assembling ◽

Vis Spectroscopy ◽

Assembly Behavior ◽

Biological Performance ◽

Type 3

3,1,2-Ruthenadicarbadodecaborane complexes bearing the [C2B9H11]2− (dicarbollide) ligand are robust scaffolds, with exceptional thermal and chemical stability. Our previous work has shown that these complexes possess promising anti-tumor activities in vitro, and tend to form aggregates (or self-assemblies) in aqueous solutions. Here, we report on the synthesis and characterization of four ruthenium(II) complexes of the type [3-(η6-arene)-1,2-R2-3,1,2-RuC2B9H9], bearing either non-polar (R = Me (2–4)) or polar (R = CO2Me (7)) substituents at the cluster carbon atoms. The behavior in aqueous solution of complexes 2, 7 and the parent unsubstituted [3-(η6-p-cymene)-3,1,2-RuC2B9H11] (8) was investigated via UV-Vis spectroscopy, mass spectrometry and nanoparticle tracking analysis (NTA). All complexes showed spontaneous formation of self-assemblies (108–109 particles mL−1), at low micromolar concentration, with high polydispersity. For perspective applications in medicine, there is thus a strong need for further characterization of the spontaneous self-assembly behavior in aqueous solutions for the class of neutral metallacarboranes, with the ultimate scope of finding the optimal conditions for exploiting this self-assembling behavior for improved biological performance.

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Synthesis, Characterisation, and Performance of Polyaniline (PANI) in Metals Sorption

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1008.222 ◽

2020 ◽

Vol 1008 ◽

pp. 222-230

Author(s):

Hamdiya Orleans-Boham ◽

Ahmed Hassan El-Shazly ◽

Marwa Farouk El-Kady ◽

Joshua Chireboah-Ansah

Keyword(s):

Aqueous Solution ◽

Aqueous Solutions ◽

Metal Adsorption ◽

Competitive Sorption ◽

Metal System ◽

Adsorption Experiment ◽

Calcium Magnesium ◽

Calcium And Magnesium ◽

And Performance

PANI was prepared in-house, characterized and utilized in the sorption of calcium, magnesium, iron, and copper in aqueous solution. The objective of this research was to evaluate adsorption of metals in mono and multi-metal in aqueous solutions onto PANI. Literature has it that, there is no record for competitive sorption of metals by PANI. The characterization of the prepared PANI confirmed with other literature that it was the Emeraldine PANI that was prepared. The results obtained after the multi metal adsorption experiment showed that PANI has a good performance in the removal of copper, iron, calcium, and magnesium, and can be credited to its' large surface area since it is a nanomaterial. Testing for the selectivity showed that the prepared nanoPANI adsorbed 95.2% of lead, 93.8% of copper and 75.8% of the iron in the single metal system.

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Rheological characterization of poly(ethylene oxide) aqueous solution under dynamic helical squeeze flow

Korea-Australia Rheology Journal ◽

10.1007/s13367-012-0033-y ◽

2012 ◽

Vol 24 (4) ◽

pp. 267-275 ◽

Cited By ~ 1

Author(s):

Jae Hee Kim ◽

Kyung Hyun Ahn

Keyword(s):

Aqueous Solution ◽

Ethylene Oxide ◽

Squeeze Flow ◽

Rheological Characterization ◽

Poly Ethylene Oxide ◽

Poly Ethylene

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Experimental Characterization of Viscosity and Thermal Conductivity of Aluminum Oxide Nanofluid

Volume 1: Heat Transfer in Energy Systems; Thermophysical Properties; Theory and Fundamental Research in Heat Transfer ◽

10.1115/ht2013-17509 ◽

2013 ◽

Author(s):

Clement C. Tang ◽

Sanjib Tiwari ◽

Matthew W. Cox

Keyword(s):

Thermal Conductivity ◽

Aluminum Oxide ◽

Effect Of Temperature ◽

Experimental Characterization ◽

Rheological Characterization ◽

Rate Range ◽

Fluid Behavior ◽

Nanoparticle Dispersions ◽

Al2o3 Nanoparticle

Experiments have been conducted to measure the dynamic viscosity and thermal conductivity of aluminum oxide (Al2O3) nanoparticle dispersions at 6% vol. in liquid water. Rheological characterization of the Al2O3–water nanofluid has shown that it exhibits a Newtonian fluid behavior for the shear rate range of 6 to 122 s−1 between 6 and 75°C. Measurements of the nanofluid thermal conductivity have been performed for temperatures between 7 and 55°C, and have been found to be 8 to 17% higher than that of water. Thermal conductivity of the nanofluid responded to temperature increase with appreciation in value. When compared with correlations available in the literature, the measured thermal conductivities are in better agreement with correlation that includes the effect of temperature.

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