Showing papers on "Viscometer published in 2020"

Viscosity Models for Drilling Fluids—Herschel-Bulkley Parameters and Their Use

Abstract: An evaluation is presented of the practical usage of the Herschel-Bulkley viscosity model for drilling fluids. If data from automatic viscosity measurements exist, the parameters should be selected from relevant shear rate ranges to be applicable. To be able to be used properly, viscosity measurements must be measured with a sufficient accuracy. It is shown that a manual reading of standard viscometers may yield insufficient accuracy. It is also shown that the use of yield point/plastic viscosity (YP/PV) as measured using API or ISO standards normally provide inaccurate viscosity parameters. The use of the Herschel-Bulkley model using dimensionless shear rates is more suitable than the traditional way of writing this model when the scope is to compare different drilling fluids. This approach makes it also easier to make correlations with thermodynamic quantities like pressure and temperature or chemical or mineralogical compositions of the drilling fluid.

A unique multilayer perceptron model (ANN) for different oxide/EG nanofluid’s viscosity from the experimental study

Abstract: In this work, different oxide-based nanofluids in ethylene glycol base fluid were prepared. The volumetric concentration of 0.2%, 0.5%, 0.8%, 1% and 1.5% of Al2O3, CeO2, and CuO nanofluid samples were used for viscosity experiment. The viscosity tests were performed on Anton Paar (SVM 3000 Stabinger) viscometer for the temperature range of 20 °C–80 °C. With the increase in temperature, the exponential variation in viscosity was observed, while the linear variation in its density. Since these oxide nanofluids have the same tendency of change in viscosity with temperature, therefore, a unique multilayer perceptron artificial neural network was utilized to predict the different oxide based nanofluid viscosity. This neural network can predict the viscosity for the different oxides nanofluids subjected to various volume concentrations, temperature, and size. The R2 value for training and testing data were 0.9998 and 0.9999. The model was validated by predicting the viscosity results from the experimental work of other researchers.

Effects of BaO on the Viscosity and Structure of a New Fluorine-Free CaO-Al2O3-TiO2-Based Mold Flux for High Titanium Steel

Abstract: Herein, the effects of BaO (i.e. 5, 10, 15 and 20 pct) on the viscosity and structures of a new fluorine-free CaO-Al2O3-TiO2-based mold flux with w(CaO pct)/w(Al2O3 pct) ratio of 1.0 are investigated using a rotary viscometer, molecular dynamics (MD) simulations, and Raman spectroscopy. The viscosity of the samples (the testing temperature is 1300 °C) decrease from 0.46 to 0.21 Pa·s as the BaO content increased from 5 to 20 pct, and the activation energy decreases from 150.7 to 119.7 kJ·mol−1, the break temperature (Tbr) decreases from 1475 K to 1429 K which are achieved as the initial testing temperature of 1300 °C decreased under the furnace cooling. With the addition of BaO, the MD simulation results suggest that the coordination numbers (CNs) of Al (Ti)-O are reduced, while Q3, Q4, and Q5 are depolymerized into Q0, Q1, and Q2. The Raman spectroscopy results illustrate that the bridge oxygens (BOs) originating from the Ti-O-Ti (Al) linkages and Q2 (Al-O−) are depolymerized into Q1 (Si-O−) and Q0 (Al-O−) as the BaO content is increased. The Raman spectroscopy results agree well with those of the MD simulation. Therefore, BaO can simplify the structure of melts and decrease the viscosity of such systems. This work not only presents a new fluorine-free CaO-Al2O3-TiO2-based mold flux, but also deepens the understandings of the role of BaO in this system.

Viscosity measurements utilizing a fast-flow microfluidic paper-based device

Abstract: Traditional microfluidic paper-based analytical devices (μPADs) use capillary action to transport fluids through a single layer of paper. While μPADs have many advantages, flow rates are typically quite slow. Fast-flow paper-based analytical devices (ffPADs) have unique and advantageous flow characteristics that differ from traditional μPADs. ffPADs have a hollow channel with paper on at least one side that generates flow rates of cm/s. Within the device, two types of flow interact with each other to create the fast flow phenomenon. In this work, we take advantage of these flow characteristics to create a viscosity measurement method for biofluids. Solution viscosity is important for a range processes from pharmaceutical formulations to clinical diagnostics. The proposed method uses a small sample volume (100 μL) without the need for reference fluids or measurements for unknown fluid properties. Additionally, the device is fabricated from paper, double-sided adhesive and transparency film, so it still possesses the advantages of traditional paper-based devices such as portability, ease of use, and low-cost. To confirm the device performance, viscosities of polyethylene glycol (PEG) solutions were measured at different concentrations and were found to be in good agreement with a commercial viscometer. Finally, viscosity measurements of artificial saliva solutions were also demonstrated to verify biofluid applicability.

Experimental study on the effect of wax inhibitor and nanoparticles on rheology of Malaysian crude oil

Abstract: In Malaysia, solid depositions of paraffin wax in the inner walls of production and transportation pipelines, and on the surface of production equipment have been identified as the utmost challenge in production and transportation of crude oil. In order to overcome the wax deposition issue, physical characterization of crude oil is crucial. In this study, the performance of wax inhibitor and nanoparticle, sodium cloisite Na+ is evaluated to determine their effects on the viscosity of crude oil using Brookfield DV-III viscometer. Nanoparticle was used along with 500, 800, 1000, 2000 and 5000 ppm of Poly (ethylene-co-vinyl acetate) (EVA) and Poly (maleic anhydride-alt-1-octadecene) (MA). Nanoparticle alone was able to lower the viscosity of crude oil to about 92.5%. EVA and MA were able to reduce the viscosity up to 88% and 86.4%, respectively while EVA and MA added to nanoparticle was able to reduce the viscosity up to about 94% and 89.2%. The blend between wax inhibitor and nanoparticle provides significant reduction in viscosity of crude oil.

Viscous flow properties and hydrodynamic diameter of phenothiazine-based redox-active molecules in different supporting salt environments

Abstract: We report viscous flow properties of a redox-active organic molecule, N-(2-(2-methoxyethoxy)ethyl)phenothiazine (MEEPT), a candidate for non-aqueous redox flow batteries, and two of its radical cation salts. A microfluidic viscometer enabled the use of small sample volumes in determining viscosity as a function of shear rate and concentration in the non-aqueous solvent, acetonitrile, both with and without supporting salts. All solutions tested show Newtonian behavior over shear rates of up to 30 000 s−1, which was rationalized by scaling arguments for the diffusion-based relaxation time of a single MEEPT molecule without aggregation. Neat MEEPT is flowable but with a large viscosity (412 mPa⋅s at room temperature), which is ∼1000 times larger than that of acetonitrile. MEEPT solutions in acetonitrile have low viscosities; at concentrations up to 0.5 M, the viscosity increases by less than a factor of two. From concentration-dependent viscosity measurements, molecular information was inferred from intrinsic viscosity (hydrodynamic diameter) and the Huggins coefficient (interactions). Model fit credibility was assessed using the Bayesian Information Criterion. It is found that the MEEPT and its charged cations are “flowable” and do not flocculate at concentrations up to 0.5 M. MEEPT has a hydrodynamic diameter of around 8.5 A, which is almost insensitive to supporting salt and state of charge. This size is comparable to molecular dimensions of single molecules obtained from optimized structures using density functional theory calculations. The results suggest that MEEPT is a promising candidate for redox flow batteries in terms of its viscous flow properties.

Viscosity Measurements of Binary and Multicomponent Refrigerant Mixtures Containing HFC-32, HFC-125, HFC-134a, HFO-1234yf, and CO2

Abstract: Viscosity measurements of ten refrigerant mixtures were conducted in the homogeneous liquid and gas phases with a vibrating-wire viscometer in the temperature range from (233 to 373) K at pressures...

Temperature and Pressure Dependence of the Viscosity of the Ionic Liquid 1-Butyl-3-methylimidazolium Acetate

Abstract: Viscosities obtained with a falling-body viscometer are reported at pressures up to 300 MPa, over the temperature range 278–353 K, for 1-butyl-3-methylimidazolium acetate ([BMIM][Ac]) samples dried...

A droplet-based microfluidic viscometer for the measurement of blood coagulation.

Abstract: A continuous microfluidic viscometer is used to measure blood coagulation. The viscometer operates by flowing oil and blood into a cross section where droplets are generated. At a set pressure, the length of the droplets is inversely proportional to the viscosity of the blood sample being delivered. Because blood viscosity increases during coagulation as the blood changes from a liquid to a solid gel, the device allows to monitor coagulation by simply measuring the drop length. Experiments with swine blood were carried out in its native state and with the addition of coagulation activators and inhibitors. The microfluidic viscometer detected an earlier initiation of the coagulation process with the activator and a later initiation with the inhibitor compared to their corresponding controls. The results from the viscometer were also compared with the clinical method of thromboelastography (TEG), which was performed concurrently for the same samples. The time to initiation of coagulation in the microfluidic viscometer was correlated with the reaction time in TEG. Additionally, the total time for the measurement of clot strengthening in TEG correlated with the time for the maximum viscosity observed in the microfluidic viscometer. The microfluidic viscometer measured changes in viscosity due to coagulation faster than TEG detected the clot formation. The present viscometer is a simple technology that can be used to further study the entire coagulation process.

Structure and Viscosity of Molten CaO-SiO 2 -Fe x O Slag During the Early Period of Basic Oxygen Steelmaking

Abstract: According to the composition variation during the initial period of basic oxygen steelmaking, ice-quenched samples of the CaO-SiO2-FexO system were prepared, and the viscosity and structure of molten slag were further analyzed by a rotary viscometer and Raman spectroscopy, respectively The results showed that Si4+ existed as Q0, Q1, Q2 and Q3 units The O2− ions led to the depolymerization of [SiO4] tetrahedrons from Q3 to Q0 units with increasing Ca/Fe ratio For Fe3+ cations, two types of [FeO4] tetrahedron and [FeO6] octahedron coexisted in the molten slag, and coordination of Fe3+ transformed from tetrahedron to octahedron with the Ca/Fe ratio increasing to 318 Viscosity of molten slag showed a continuous decrease because of the simpler network Moreover, to clarify the viscosity-structure relationship, the viscosity estimation equation applied to the CaO-SiO2-FexO-based system was established in terms of the deconvolution result of the melt structure

Hand-held, automatic capillary viscometer for analysis of Newtonian and non-Newtonian fluids

Abstract: Despite advances in measuring fluid viscosity, we still lack portable viscometers to analyze shear rate-varying fluid characteristics in the form of open-source hardware that non-expert users can easily make and use We present a hand-held, automatic capillary viscometer, termed "Viscopette", which can be fabricated simply by assembling globally available mechanical (a stepper motor and an inline pressure sensor), fluidic (a positive-displacement pipette and a cut tubing piece), electronic (an Arduino board) parts in a 3D-printed housing The Viscopette is specifically designed to improve user experience by adopting how to use commercial micropipettes, and fits within 73 cm × 73 cm × 388 cm (without the cut tubing piece) with an overall weight of 437 g for portable use By exploiting the high level of controllability of the open-source microcontroller, the Viscopettes enables time-varying shear-rate (or flow-rate) control for viscosity analysis, and simple viscosity measurement by calculating the ratio of a pressure value measured using the inline pressure sensor and a set flow-rate condition With the advantages of ease-of-use, portability, and shear-rate controllability, we demonstrate the Viscopette's ability to accurately analyze Newtonian and non-Newtonian fluids Our method addresses the unmet need in portable, high-performance viscometers suitable for use as an open-source equipment, which can facilitate on-site, accurate viscosity analysis even by non-expert users

Microfluidic Viscometer Using a Suspending Micromembrane for Measurement of Biosamples.

Abstract: The viscosity of biofluids such as blood and saliva can reflect an individual’s health conditions, and viscosity measurements are therefore considered in health monitoring and disease diagnosis. However, conventional viscometers can only handle a larger liquid volume beyond the quantity that can be extracted from a person. Though very effective, micro-sensors based on electrokinetic, ultrasonic, or other principles often have strict requirements for the supporting equipment and complicated procedures and signal processing. Sample contamination is always an important issue. In this paper, we report a microfluidic viscometer requiring a small volume of biosamples (<50 µL) and straightforward operation procedures. It is fabricated with low-cost and biocompatible polymeric materials as one-time-use devices, such that contamination is no longer the concern. It contains a suspending micromembrane located along a microchannel. Under a steady driving pressure, the membrane displacement is a function of viscosity of the liquid sample being tested. We derived a simple analytical relation and perform a simulation for converting the membrane displacement to the sample viscosity. We conducted experiments with liquids (water and mineral oil) with defined properties to verify such a relation. We further applied the micro-viscometer to measure bovine blood samples with different hematocrit levels. It can be concluded that the microfluidic viscometer has a high compatibility with a broad range of biomedical applications.

Densities and Viscosities of Ionic Liquid with Organic Solvents

Abstract: The ionic liquid (IL) of 1-hexyl-3-methylimidazolium acetate is widely used in chemical and bio-chemical processes. In this work, due to the high viscosity of IL, the promising chemicals (i.e., N, N-dimethylacetamide, N, N-dimethylformamide, and dimethyl sulfoxide) were selected as the additives to lower IL viscosity. The thermophysical properties of density and viscosity for IL with solvents were measured using a digital vibrating U-tube densimeter and an Ubbelohde capillary viscometer from 303.15 to 338.15 K at atmospheric pressure (0.0967 MPa), respectively. The influences of the solvents on the thermophysical properties of ionic liquid were quantitatively studied. Furthermore, based on the measurement values, the derived properties of excess molar volumes, thermal expansion coefficient, and the energy barrier were calculated, and the results showed that the mixture composition had great impact on excess volume change and viscosity. The hard-sphere model was employed to reproduce the viscosity. The infrared spectroscopy was performed to study the chemical structure to further understand the interactions between IL and the solvents.

Effect of BaO on the viscosity and structure of fluorine-free calcium silicate-based mold flux

Abstract: The effect of BaO on the viscosity and structure of fluorine-free calcium silicate-based mold flux was studied using a rotary viscometer, molecular dynamics (MD) simulation, and Raman spectroscopy. The results demonstrated that the viscosity, activation energy, and break temperature of the samples decreased with the addition of BaO. The MD simulation revealed that the network breakers of BaO readily offered O2− to decrease the degree of polymerization of the network formers of SiO2 and Al2O3 in melts. The results of the Raman spectroscopy demonstrated that the complex network structure of [SiO3]2− (chain) and [Si2O5]2− (sheet) was depolymerized to the simple structure of [Si2O7]6− (dimer) and [SiO4]4− (monomer) with an increasing content of BaO. The results of the Raman spectroscopy were consistent with the MD simulation; thus, in conclusion, the complex network structure was depolymerized to the sample structure, resulting in a decrease in viscosity with the addition of BaO.

Hot Mixing Behavior and Curing Process of Epoxy Asphalt

Abstract: A new hot mixed epoxy asphalt system was developed The reaction process of epoxy resin was characterized by Fourier transform infrared spectroscopy (FTIR) The viscosity was investigated by Brinell viscometer when epoxy resin was mixed with asphalt The glass transition temperature (Tg), homogeneity, thermal stability and viscoelasticity of epoxy asphalt were analyzed by differential scanning calorimetry (DSC), metallographic microscope, thermogravimetric (TG) and dynamic mechanical analysis (DMA) The results showed that the viscosity of epoxy resin modified asphalt reached 1 000 mPa·s for more than 180 minutes at 180 °C, while the best construction process is mixing at 180 °C for 2 hours and curing at 60 °C for 4 days The particle size of asphalt is less than 50 µm In addition, the mechanical properties of the materials are uniform within the specified pavement thickness

Density and Viscosity of CO 2 + EthanolBinary Systems Measured by a Capillary Viscometer from 308.15 to 338.15K and 15 to 45 MPa

Abstract: Density and viscosity of CO2 + ethanol binary systems were measured by a high-pressure capillary viscometer at different ethanol mole fractions of 0, 0.067, 0.135, 0.203, 0.271, and 1 with temperat...

Determination of intrinsic viscosity of native cellulose solutions in ionic liquids

Abstract: The weight-average molecular weights of six native cellulose samples in ionic liquids were determined through steady shear viscosity measurements in the ionic liquid butyl methyl imidazolium chloride. The intrinsic viscosity [ η ] in ethyl methyl imidazolium acetate (EMImAc) is measured using a gravity-driven glass capillary viscometer and found to be independent of temperature in the range of 30–80 °C, disproving a literature report of [ η ] in EMImAc, exhibiting a strong temperature dependence. Findings are contrasted with values of intrinsic viscosity in cupriethylenediamine hydroxide, the most widely used solvent to dissolve and analyze the molecular weight of cellulose pulps in industry. Differences are tentatively attributed to the different temporary association properties of cellulose chains in the two solvents. Finally, it is demonstrated that cellulose adsorbs at the air/solution interface in three different ionic liquids to create a viscoelastic liquid interfacial layer of higher concentration. Adsorption at the air/solution interface gives an extra contribution to the measured torque in various rotational rheometer geometries, which apparently simply adds to the torque from the pure bulk solution.

New Technologies for Measuring Viscosity: Using Mobile Applications

Abstract: A new technology for viscosity measurements with using mobile applications was suggested. The technology is based on a known method of a viscosity measurement trough defining characteristics of ball movement in a viscous environment, but its difference that the character of ball movement which setting by an external magnetic field. The technology provides for the processing of primary measurement signals, which taken from measuring inductors, using installed on a smartphone software conjugate with a measuring device. This allows to significantly reducing the cost of equipment which designed to measure viscosity. These systems, designed to measure viscosity, are in fact the first step to create a whole range of different laboratory devices for currently use, including in the chemistry of high molecular weight compounds.

Experimental and Theoretical Investigation of Thermophysical Properties of Synthesized Hybrid Nanofluid Developed by Modeling Approaches

Abstract: Although, titanium oxide (TiO2) has appropriate mechanical and chemical stability used in different applications, its thermal conductivity slightly increases with an increasing temperature and concentration compared with other metal oxides such as aluminum oxide (Al2O3). Thus, synthesized aluminum oxide nanoparticles were incorporated on the surfaces of titanium oxide in ultrasonication condition with purpose of thermophysical properties modification. The scanning electron microscopy and X-ray diffraction were used to investigate the structure and morphology of synthesized nanocomposite. The impact of variables (temperature, volume fraction and nanoparticle size) on the thermal conductivity and viscosity of prepared hybrid nanofluid was investigated using KD2Pro instrument and Brookfield DVII viscometer, respectively. Results showed a significant improvement of thermophysical properties of prepared hybrid nanofluid, compared to water or untreated titanium oxide–water. The results showed that three mentioned variables considerably affect the thermophysical properties of hybrid nanofluid; as an increasing volume fraction, reducing nanoparticle size and temperature led to an increasing viscosity while enhanced thermal conductivity was resulted from an increasing nanofluid volume fraction and temperature, and a decreasing nanoparticle size. This was confirmed using two computer-modeling approaches, which allow optimization of the thermophysical properties of hybrid nanofluid. Modifying Response Surface Methodology-Central Composite Design (RSM-CCD) estimated accurately the optimal conditions for thermal conductivity and viscosity. The best artificial neural network model was chosen based on its predictive accuracy for estimation of thermophysical properties; having seven neurons in hidden layer and minimum error, demonstrated the most accurate approach for modeling the considered task.