Shear Thickening Properties Research Articles

An approach to describe the shear-thickening viscosity of cement paste incorporating microfines of manufactured sand

This paper investigates the mechanisms affecting the viscosity in shear thickening regimes of cement pastes. Limestone, slate, and tuff microfines (≤125 μm) with different physical properties obtained in the processing of manufactured sand were employed as additional mineral materials to cement pastes prepared with variable dosages of polycarboxylate ether superplasticizer (PCE) and water-to-cement mass ratios (W/C) of 0.40 and 0.275. Test results show that the addition of microfines reduced the shear thickening properties of cement pastes at a fixed PCE dosage, mainly due to a smaller growth of particle inertial interactions from the pseudo-Newtonian plateau to a given shear rate. But the shear thickening reduction did not always cause a lower increase of the apparent viscosity, Δηthicγ̇, for paste mixtures made with 0.275 W/C, due to a greater enhancement of particle friction contacts. Meanwhile, the shear thickening performance at a given mini-slump flow increased by using the microfines, given the stronger particle friction contacts caused by the increased flow index of Herschel-Bulkley model. This corresponded to a greater Δηthicγ̇ of the pastes. A prediction model of Δηthicγ̇ was proposed based on the mechanisms of particle inertia forces and friction contacts. The model can efficiently characterize particle frictional contact interactions in shear thickening regimes by taking into consideration the flow index, particle packing density, and solid volume fraction, regardless of the W/C and the content and type of microfines.

The Influence of UV Radiation Aging on Degradation of Shear Thickening Fluids.

Shear thickening fluids (STFs) are innovative materials that can find applications in smart body armor. However, the usage of STFs is limited by the aging of these materials. This work aims to analyze the influence of UV radiation on the aging process of STFs. The investigation was done experimentally, and artificial aging was applied to investigate the impact of UV radiation on the properties of STFs. The shear-thickening properties of obtained STFs were confirmed by viscosity measurements. The STFs based on PPG425, PPG2700, and KE-P10 exhibited a very high maximum viscosity of up to 580.7 Pa·s and 3313 Pa·s for the STF425 and STF2700, respectively. The aging of the obtained STFs caused the liquid matrix degradation, causing damage to the STFs and their change from liquid into solid. Furthermore, the FT-IR, 1H NMR, and 13C NMR spectroscopies were used for the confirmation of the breakdown of STFs. The FT-IR spectroscopy revealed the appearance of carbonyl groups in STFs after aging. Moreover, 1H NMR and 13C NMR spectroscopy confirmed the formation of the typical groups containing carbonyl groups. Our results demonstrate that STFs are UV light-sensitive and may lose their properties during storage.

Mechanical Properties and Mechanism Analysis of Magnetorheological Shear Thickening Colloid

Magnetorheological shear thickening material is a new type of composite material, which has both magnetorheological properties and shear thickening properties.In this paper, the influence of two important factors to the magnetorheological properties and shear thickening properties have been studied. The factors includ boric acid status and the ratio of polydimethylsiloxane to post-treatment boric acid in the material fabrication process .The article also systematically analyzed the action mechanism of the magnetorheological shear thickening material, mainly explained the internal mechanism of cycle that the material changes from the initial chaotic state to the formation of a three-dimensional micro-magnetic particle chain network, and then returns to the initial state. The study of material preparation parameters provides an experiment basis which can provide parameter for the preparation of materials with specified properties.The clarification of the material mechanism provides an idea for the subsequent quantitative analysis of the action of carbonyl iron particles in the material under the three force systems, and provides a theoretical basis for the subsequent study of the material’s kinetic model.

Theoretical analysis of modified eyring powell fluid flow

Background: Applications of Eyring-Powell fluid is found in paint industries, pharmaceutical companies and armour construction. Eyring-Powell fluid models are able to model Newtonian and shear-thinning fluids under different conditions, but researchers have reported seemingly contradicting results based on the effects of Eyring-Powell parameter on flow velocity. Methods: This paper shows that Eyring Powell fluid can also exhibit shear-thickening properties when certain conditions are imposed. By introducing this condition on Eyring-Powell model, a new class of Modified Eyring-Powell fluid is presented in this study, which clearly shows why different results are obtained by different researchers. A theoretical analysis of the heat transfer is carried out on the flow of MEP on a linearly stretching flat plate and the results are depicted as graphs and tables. Significant Findings: It is found that increasing Prandtl number causes a decrease in the temperature. Under shear-thinning condition, increasing the Eyring-Powell parameters leads to a decrease in both skin-friction coefficient and heat transfer rate. Under shear-thickening condition, increasing the Eyring-Powell parameters leads to an increase in both skin-friction coefficient and heat transfer rate.

Rheological and Technological Aspects in Designing the Properties of Shear Thickening Fluids.

This work focuses on shear thickening fluids (STFs) as ceramic–polymer composites with outstanding protective properties. The investigation aims to determine the influence of raw material parameters on the functional properties of STFs. The following analyses were used to characterize both the raw materials and the STFs: scanning electron microscopy, dynamic light scattering, matrix-assisted laser desorption/ionization time-of-flight, chemical sorption analysis, rheological analysis, and kinetic energy dissipation tests. It was confirmed that the morphology of the solid particles plays a key role in designing the rheological and protective properties of STFs. In the case of irregular silica, shear thickening properties can be obtained from a solid content of 12.5 vol.%. For spherical silica, the limit for achieving shear thickening behavior is 40 vol.%. The viscosity curve analysis allowed for the introduction of a new parameter defining the functional properties of STFs: the technological critical shear rate. The ability of STFs to dissipate kinetic energy was determined using a unique device that allows pure fluids to be tested without prior encapsulation. Because of this, it was possible to observe even slight differences in the protective properties between different STFs, which has not been possible so far. During tests with an energy of 50 J, the dissipation factor was over 96%.

Coriolis effects on MHD flow of MEP fluid over a non-uniform surface in the presence of thermal radiation

The study of electrically conducting Eyring-Powell fluid flow across a rotating surface has practical applications in the exploitation of liquid metals, manufacturing of ship propellant, production of paints, greases, and toothpaste. The Modified Eyring-Powell (MEP) fluid is the Eyring-Powell fluid equipped with a parameter that regulates the shear thickening and shear thinning properties. In this paper, MEP flow is investigated over a rotating and stretching surface under the influence of thermal radiation and magnetic field. The model that governs the flow of electrically conducting MEP fluid over a stretching rotating surface with non-uniform thickness in the presence of thermal radiation is formulated and non-dimensionalised. The dimensionless governing equations are solved numerically; with the results depicted as graphs. It is found that the primary velocity is reduced with increasing rotation, magnetic field strength and MEP parameter but increases with velocity index.

Hyaluronic acid sustains platelet stability with prolonged growth factor release and accelerates wound healing by enhancing proliferation and collagen deposition in diabetic mice

Platelet Rich Plasma (PRP) has gained significant attention in diabetic wound management due to the presence of growth factors. However, its short self-life ex vivo limits its clinical use. Among the biopolymers hyaluronic acid (HA), offers higher biocompatibity with bioactivity and ideal polymer properties for delivery of the cell based products. Hence, here HA gel matrix was prepared to hold PRP to prolong the growth factor stability. PRP prepared from healthy donors was used after characterizing total platelets (3.0 ± 0.17 × 106 cells/mL) and PDGF-BB levels (156.37 ± 1.73 ng/mL). This was subsequently entrapped in1:3 ratios of PRP:HA gel. The prepared gels were stored at different conditions to study growth factor stability. The prepared gels showed near neutral pH (6.99) with shear thickening properties. On the 15th day of storage at −20 °C temperature, the PDGF-BB levels in the PRP stored directly reduced by 35.98% while HA-PRP gels it reduced by 20.91%. Considerably higher cell proliferation (43.11%) and migration (85%) were observed on treatment with gels stored at −20 °C for 15 days compared to the PRP stored directly. Topical application of the gels on diabetic mice showed complete wound contraction by 15th day compared to untreated groups. Enhanced collagen and cytokeratin 10 depositions were observed owing to the synergistic effect of the polymer protein combination. These results are suggestive of HA-PRP gels as topical applicants for treating diabetic wounds and using PRP into a mainstream treatment strategy in clinical practices.

Effect on rheology and frying stability of edible oil before and after addition of fenugreek seeds

Rheological parameters of vegetable oils showed great changes during frying. The correlation between rheological behavior and viscosity measurements during frying can give a good overall estimate of frying oil quality. In the present study, rheological properties of rice bran oil (RBO) and soybean oil (SBO) during deep-frying of 13 ​min were investigated for consecutive 1st, 2nd, 3rd, and 4th frying at an interval of one week. To enhance the frying stability of RBO and SBO, fenugreek seeds (Trigonellafoenum graecum) was added during frying. The shear stress versus shear rate data was fitted to Newtonian and Herschel-Bulkley rheological models. The flow behavior of RBO and SBO with and without fenugreek seeds in before and after frying were measured at 30 ​± ​2 ​°C. The increase in viscosity, acid values and flow behavior index (n) with frying times for both RBO and SBO can be controlled with the addition of fenugreek seed up to 3rd frying with n ​< ​1 values, where without fenugreek seeds for RBO and SBO it showed a shear thickening properties (n ​> ​1) after 2nd and 3rd frying respectively.

The rheological properties of multifunctional shear thickening materials and their application in vehicle shock absorbers

A composite with both shear thickening (ST) and magnetorheological (MR) properties is fabricated by composing carbonyl iron powder into an ST matrix. The rheological properties are studied and the relative ST effect of the samples prepared under vacuum and non-vacuum conditions are compared. Then, the hydraulic oil in a vehicle hydraulic shock absorber is replaced with ST gel and ST fluid. The compression and rebound forces of the shock absorber containing hydraulic oil and ST fluid are tested and compared. Equal amounts of multifunctional ST fluid (MSTF, self-made) and MR fluid (self-made) are poured into an MR shock absorber and the performances are compared against the commercial MR shock absorber. Finally, the comprehensive performance and forces are improved by replacing SiO2 with the silica powder due to the smaller mean particle size.

Simulation of Shear-Thickening Liquid Transfer between U-Shaped Cell and Flat Plate

Based on the actual measurement of the shear-thickening properties of water-based inks, in order to improve the ink transfer rate, the PLIC (Piecewise Linear Interface Construction) interface tracking method and the VOF (Volume of Fluid) method are used to simulate the transfer process of the shear-thickening liquid between the U-shaped cell and the upwardly moving plate. The effects of substrate surface wettability, cell contact angle, and cell depth on liquid transfer were studied. The results showed that all can increase the liquid transfer rate, and the change of the cell contact angle also led to the difference in the breaking time of the liquid filament. In addition, the shallow plate effect was discovered in the study of cell depth. The shallow plate effect is a phenomenon by which the amount of liquid transferred and the liquid transfer rate are greatly improved when the depth of the cell decreases to a certain limit value. In addition, for the U-shaped cell, the optimization method combining the shallow printing plate effect and fillet can greatly improve the liquid transfer rate and solve the undesirable problems such as plate blocking. After optimization, a liquid transfer rate of about 85% can be achieved.

Abuse-Tolerant Electrolytes for Lithium-Ion Batteries.

Safety issues currently limit the development of advanced lithium‐ion batteries (LIBs) and this is exacerbated when they are misused or abused. The addition of small amounts of fillers or additives into common liquid electrolytes can greatly improve resistance to abuse without impairing electrochemical performance. This review discusses the recent progress in such abuse‐tolerant electrolytes. It covers electrolytes with shear thickening properties for tolerating mechanical abuse, electrolytes with redox shuttle additives for suppressing electrochemical abuse, and electrolytes with flame‐retardant additives for resisting thermal abuse. It aims to provide insights into the functioning of such electrolytes and the understanding of electrolyte composition‐property relationship. Future perspectives, challenges, and opportunities towards practical applications are also presented.

Non-edible/waste cooking oil–derived sustainable green multifunctional copolymeric additives for mineral base oil

The greener additives have drawn considerable awareness in the lubricant industry due to their biocompatibility and multifunctional behaviour compared to conventional additives. In this study, novel multifunctional copolymer additives (MCAs) were synthesised from non-edible/waste cooking oil with stearyl methacrylate via addition polymerisation in the presence of benzoyl peroxide as a free radical initiator. The copolymeric additives derived from castor oil and waste cooking oil are named as MCA-1 and MCA-2, respectively. The prepared additives have been characterised by routine NMR and FT–IR spectroscopy, whereas the molecular weight and thermal-oxidative stability of the copolymers were determined by gel permeation chromatography (GPC) and thermogravimetric analysis (TGA) respectively. Doping of the synthesised multifunctional green additives in terms of viscosity index improver (VII), pour point depressants (PPD) in base oil (N–150) have been determined using standard ASTM methods. The rheological behaviour of the doped base oil was examined using Anton Par MCR–72 in different concentrations of additive, viz. 1%, 1.5%, and 2% (w/v). The performance of the doped oil was compared with base oil. The additives were found to show the multifunctional behaviour in terms of pour point depressant, viscosity index improver, and rheology modifier. The improvement in viscosity with respect to base oil is in close agreement with the rheological study, which shows shear-thickening property with an increase in the concentration of additive. The significance of the study lies, in fact, the viscosity of the lubricant increases with shear rate and then decreases, making it suitable under the varying condition of temperature. Moreover, waste cooking oil can be used as a promising alternative for the preparation of environmentally friendly multifunctional additives. It is cheaper, readily available, renewable, and non-edible oil over conventional, expensive edible oil for the formulation of lubricants.

Enhancement of foam stability parallel with foamability of the foam stabilized by sodium caseinate-based complex: Octenyl succinate starch acting a dual role

Interaction among the multiple components play a crucial role in regulating the foam properties. In this work, the relationship among the interaction of sodium caseinate (SC)/tannin acid (TA)/octenyl succinate starch (OSA-Starch), rheological properties, and the resultant foam properties was investigated. The results of the phase diagram show that the complexes formed by SC and OSA-Starch through electrostatic interactions depend on pH changes. At pH 4.0 and 5.0, the OSA-Starch constraints the binding between SC and TA, however, it promotes the formation of soluble complexes at pH 6.0. Meanwhile, the OSA-Starch advance the diffusion of SC-based complex (SC or SC/TA) from the bulk phase to the air/water interface and the rearrangement on the interface due to the depletion mechanism, which improve foamability and maintain admirable foam stability. The shear-thickening properties of the foam stabilized by SC/TA/OSA-Starch contribute to foam stability. Finally, the micro-rheology results show that the TA acts as a bridge to connect the SC and OSA-Starch, forming a viscoelastic film around the bubble and maintaining admirable foam stability. This study provides a theoretical basis for the exciting opportunities of the ternary-component complex in interface-dominated food systems.

Rheological and deformation behavior of natural smart suspensions exhibiting shear thickening properties

Shear thickening fluid (STF) is a very interesting and promising material in several application fields where a different mechanical is demanded based on loading rates, like body armor and vibration insulators. Cork is a natural cellular material by excellence, filled with well-known beneficial effects in terms of insulation and also interesting crashworthiness properties. In this work, cork grains of very small size (0.5–1.0 mm) are added to two different shear thickening suspensions, one of them a fully natural water and cornstarch, and the other based on fumed silica and polyethylene glycol. The rheology of these eco-friendly suspensions was investigated and the influences of including cork grains were discussed. In addition, microscopic analyses were carried out to observe the deformations at each component during the shear thickening phenomenon. Cork grains reduce the load-carrying capacity in the suspensions due to the deformable characteristics of cork. For this reason, shear thickening properties are suppressed in the mixtures. Despite this, it is possible to state that viscosity increase in the mixtures leads to strong particle contacts, and thereby resulting in particle deformations in the main constituent powder as well as in the cork additives due to their softer structures.

Finite Volume Method for Fractional Maxwell Viscoelastic Fluid Over a Moving Plate With Convective Boundary Condition

Abstract A novel finite volume method about the boundary layer flow and heat transfer of fractional viscoelastic fluid over a moving plate with convective boundary condition is developed. The fractional Maxwell model and fractional Fourier's law are employed in the constitutive relations. Numerical solutions are obtained and validated by exact solutions of special case with source terms. The effects of fractional parameters on the flow and heat transfer characteristics are analyzed. Results show that the viscoelastic fluid performs shear-thickening property with the increase of fractional parameter. Moreover, the variations of the average Nusselt number demonstrate that the viscoelastic fluid characterized by fractional Fourier's law has short memory in heat conduction process.

Rheological modeling of both shear-thickening and thinning behaviors through constitutive equations

Shear-thickening and thinning behaviors are often observed in the rheological measurements of dilute surfactant solutions with drag-reducing ability in wall-bounded turbulent flows. This study proposes a simple rheological modeling method based on combining constitutive equations, such as Giesekus and FENE-P models, with a fluidity equation to determine both thickening and thinning behaviors in simple shear flows simultaneously. The Giesekus and FENE-P models, which are typically used in numerical studies on turbulent drag reduction, cannot capture such complex behaviors. However, the proposed models, called f-Giesekus and f-FENE-P models, can predict the shear-thickening properties. The developed models are inspired by the Bautista–Manero–Puig model, where the Oldroyd-B model (upper-convected Maxwell model) is coupled with the fluidity equation. Parametric studies prove that the proposed models can accurately predict both the shear-thickening and shear-thinning properties. Notably, the f-FENE-P model shows prominent flexibility to determine the plateau region of the shear viscosity as a function of the shear rate. We verify that the analytical solutions of the f-FENE-P model agree with the experimental data of the shear viscosity in dilute drag-reducing surfactant solutions, except for the remarkable steep increase in the shear viscosity. The start-up shear flow is also studied to confirm various transitions accompanied by the overshoot and undershoot of the f-FENE-P model.

Rheological, Physico-chemical, and Surface-Active Properties of Gelatin Extracted from Bigeye Tuna (Thunnus obesus) Skin Waste

ABSTRACTIn the present investigation, bigeye tuna (Thunnus obesus) skin waste was utilized for the extraction of gelatin. Physico-chemical, rheological, and surface-active properties of the obtained gelatin were assessed. Proximate compositional analysis of tuna skin gelatin recorded high protein content of 88.6% and low levels of fat and ash contents. The isoelectric point (IEP) of tuna skin gelatin was around 6.24. Amino acid profiling recorded a glycine [31.7%] higher proportion, followed by imino acids (hydroxyproline + proline) [18.4%], and alanine [12.2%]. The electrophoretic pattern of purified gelatin exhibited three major bands (β, α1, and α2) with wider molecular weight distribution in the range of 200–120 kDa. The Fourier Transform Infrared (FT-IR) spectra of gelatin also confirmed the bands corresponding to α helix, β sheet, and random coil structures. The rheological studies of tuna skin gelatin revealed Newtonian and shear thickening properties. The method of extraction and assessment of its characteristic properties could be useful in the field of formulation of functional foods, nutraceutical, and biomedical applications.

Rheological properties and stability of shear thickening fluids based on silica and polypropylene glycol

Rheological behavior and structural stability of shear thickening fluids (STFs) based on amorphous silica KE-P50 (500–600 nm) and polypropylene glycol, with molar mass 2000 g mol−1, were studied. The static and dynamic rheological measurements were performed using rheometer ARES and stability tests were carried out using the static multiple light scattering (S-MLS) method. The preliminary tests were performed for the STFs having 50–55 vol% of silica and the detailed studies were carried out for two fluids, with 50 and 53 vol% of silica, respectively. All the STFs studied exhibit shear thickening properties. Both, the zero-shear-viscosities and maximal viscosities increase with growing silica content. For the shear rates studied the viscous component of the shear modulus dominates over the elastic one. S-MLS tests showed that both the suspensions studied exhibit excellent stability over the 8 days of the test. The synthesized STFs can be used as a component of flexible energy absorbing and protecting structures.

Measuring the thixotropy of conventional concrete: The influence of viscosity modifying agent, superplasticiser and water

The study sets out to evaluate the thixotropy of conventional concrete containing rheology modifiers using various methods of rotational rheometry. Five mixes were examined: the control, two mixes with viscosity modifying agent (VMA) and superplasticiser (SP) respectively, a mix with combined viscosity modifying agent and superplasticiser (VMA + SP) and the last mix with an increase in water content. These mixes were formulated to achieve concrete with varying rheological properties. Tests were carried out to examine the evolution of rheology parameters (static yield stress, dynamic yield stress and plastic viscosity), thixotropy index, shear thinning and thickening, flocculation properties, torque decay pattern (with a subsequent drop in apparent viscosity), and hysteresis loop. Results show that conventional concrete known to be a shear thinning and thixotropic material, can possess anti-thixotropic (rheopexy) and shear thickening properties depending on the condition pre-history, resting time, shearing rate and inclusion of rheology modifiers. These factors also influence the magnitude of the thixotropy but not necessarily the evolution of thixotropy. Inclusion of VMA in conventional concrete had only slight influence (both increasing and decreasing depending on the method of measurement) on its thixotropic behaviour while the inclusion of SP, VMA + SP and increased water considerably influenced concrete’s thixotropic behaviour in a similar pattern. However, each rheology modifiers had its unique influence. VMA significantly improves the evolution of concrete’s viscosity; inclusion of SP tends to result in a rheopectic concrete; addition of VMA + SP and pre-shearing of concrete may result in an unstable thixotropy, while SP can initially dominate the thixotropic behaviour of concrete containing both VMA and SP, VMA’s influence may later surpass that of SP; more water in concrete tends to result in a lesser rate of thixotropic structure breakdown.

A new view on improving the preparation efficiency of shear thickening fluid

In this paper, the relationship of rheological properties, particle size and particle size distribution of dispersed phase silica at different blending times during the preparation of STF was studied in detail. It is found that with the increase of blending time, the initial viscosity η0 of STF decreases, the critical shear rate γc increases, the maximum thickening viscosity ηm decreases, the thickening ratio decreases and the shear thickening effect of the system shows a weakening trend. On the other, the volume average particle size of silica decreases gradually and finally reaches a stable value. The particle size distribution changed from double-interval distribution to single-interval distribution. The variation of shear thickening properties with blending time was explained by combining Cluster and Jamming theory. It is considered that the preparation of STF can be completed when the suspension is transparent and has a uniform viscosity. It is believed that this will play an important role in improving the efficiency of STF preparation and will be of great help to realize industrialized production of STF in the future.