Synthesis and rheological characteristics of high viscosity linear polysiloxane carrier fluid-based magnetorheological fluids

2021 ◽  
Author(s):  
Lei Xie ◽  
Young-Tai Choi ◽  
Changrong Liao ◽  
Zhi Zeng ◽  
Norman M Wereley
Keyword(s):  
Shear Rate ◽  
Rheological Properties ◽  
Particle Concentration ◽  
High Viscosity ◽  
Magnetorheological Fluids ◽  
Test Method ◽  
Fluid Viscosity ◽  
Rheological Characteristics ◽  
Carrier Fluid ◽  
Field Dependent

Abstract This study addresses the synthesis and field-dependent rheological characteristics of novel magnetorheological fluids (MRFs) using high viscosity linear polysiloxanes (HVLPs) as a carrier fluid. First of all, the components and preparation of novel HVLP-based MRFs (HVLP MRFs) were explained in detail and the microscopic images of each component were taken by using scanning electron microscope (SEM). Four HVLP MRF samples with different particle volume fractions of 10, 15, 20, and 26 vol% in the same HVLP carrier fluid viscosity of 800 Pa·s were synthesized to investigate the particle concentration effect on their field-dependent rheological properties. In order to understand the effect of the carrier fluid viscosity, two more HVLP MRF samples with different HVLP viscosities of 140 and 440 Pa·s in the same particle concentration of 26 vol% were also fabricated. In addition, the temperature effect on HVLP MRFs was studied by using the sample with 26 vol% in particle concentration and 140 Pa·s in HVLP viscosity under different operating temperatures of 25, 40, 55 and 70℃. The flow curve measurements of shear stress versus shear rate in the magnetic fields were conducted by using controlled shear rate (CSR) test method with a commercial parallel-plate type rotational rheometer. From the flow curves, the field-dependent rheological properties of HVLP MRFs including static and dynamic yield stresses and the dynamic range (ratio of field on to field off yield stress) were obtained. These material characteristics were then examined as a function of varying particle concentration, varying carrier fluid viscosity, and varying temperature. A conventional commercial MRF (i.e., Lord MRF-126CD) was adopted for comparison study and its rheological properties under different temperatures were also measured and compared with those of HVLP MRFs. Using HVLP carrier fluids, it was demonstrated that the HVLP MRFs exhibited much greater suspension stability than the conventional commercial MRF.

ANALYSIS OF THE POTENTIAL USAGE OF SELECTED MAGNETIC FLUIDS IN THRUST SLIDE BEARINGS

Tribologia ◽  
2016 ◽  
Vol 269 (5) ◽  
pp. 41-49 ◽  
Author(s):  
Wojciech HORAK ◽  
Józef SALWIŃSKI ◽  
Marcin SZCZĘCH
Keyword(s):  
Magnetic Field ◽  
Rheological Properties ◽  
Mechanical Energy ◽  
Magnetic Fluids ◽  
Magnetorheological Fluids ◽  
Machine Design ◽  
Rheological Characteristics ◽  
New Horizons ◽  
Controlled Systems ◽  
Ferromagnetic Fluids

Magnetic fluids are substances whose rheological properties can be actively influenced by treatment with a magnetic field. Two main types of magnetic fluids can be distinguished: ferromagnetic fluids, and magnetorheological fluids. Ferrofluids are mostly used in sealing engineering, whereas magnetorheological fluids are usually applied in controlled systems for the dissipation of mechanical energy, like brakes and dampers. The ability to control the rheological properties of magnetic fluids opens new horizons for development in machine design, among others in the areas of bearing engineering. The paper presents a comparative analysis of the rheological characteristics of selected magnetic fluids with a focus on the possible areas of the application of these substances in bearing engineering.

Preparation of Magnetorheological Fluid and Study on Its Rheological Properties

2014 ◽  
Vol 13 (02) ◽  
pp. 1450009 ◽  
Author(s):  
Shreedhar Kolekar
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Rheological Properties ◽  
Magnetorheological Fluid ◽  
Magnetic Flux Density ◽  
Iron Loading ◽  
Iron Particles ◽  
Mr Fluid ◽  
Carrier Fluid ◽  
System Type

The present paper focuses on preparation and process of the magnetorheological (MR) fluid whose carrier fluid is silicone-based oil and its additive is the commercial grease with different concentration of iron particles. General properties of MR fluid are discussed and rheological properties like shear rate, shear stress, viscosity of MR fluid can be found by using cone-and-plate sensor system-type rheometer. The result shows that shear stress as a function of magnetic flux density and viscosity does not strictly scale with iron loading.

The Rheological Properties of Nanoscale Fluid

2009 ◽  
Author(s):  
JiaPeng Li ◽  
Yunfei Chen ◽  
Min Chen ◽  
Changzheng Xiang ◽  
Zan Wang
Keyword(s):  
Shear Rate ◽  
Charge Density ◽  
Surface Charge ◽  
Rheological Properties ◽  
Shear Viscosity ◽  
Surface Density ◽  
Surface Charge Density ◽  
Fluid Film ◽  
Dynamics Simulation ◽  
Fluid Viscosity

Nonequilibrium molecular dynamics simulation is used to simulate the rheological properties of the nanoscale fluid. A physical model of the “bulk – nanochannel – bulk” that resembles a fluid film confined between two solid walls was simulated. The simulation is performed at variable wall speeds, nanochannel heights and surface charge densities. Simulation results indicate that the effective densities of water decrease with the size as the channel size below 1 nm when the surface charge density is −0.30 C/m2. And it is also demonstrated that the water density increases with the surface charge density. The fluid viscosity keeps at around 1.78 cp when the thickness of the film more than 1.5 nm, the −0.30 C/m2 surface charge density and the 5×1010 S−1 shear rate, which is quite close to the bulk value. The fluid viscosity keeps at around 1.69 cp when the surface charge density is −0.15 C/m2, and 1.28 cp when the surface density is 0 C/m2. In addition, the shear rate shows strong influence on the nanoscale fluid film. Compare to the surface density −0.30 C/m2 and −0.15 C/m2, the fluid density of the 0 C/m2 has different properties when the shear rate varied from 0.1×011 S−1 to 1.0×1011 S−1. Especially, when the nanochannel height is 0.8 nm, the shear viscosity begins to increase and reach the peak when the shear rate is 0.2×1011 S−1, then the shear viscosity decreases with the shear rate increase. The shear viscosity of the height of 2.5 nm and 3.0 nm show a constant value which is quite close to the bulk value, and shear viscosity of 1.5 nm height increases and reaches plateau when the shear rate exceeds 0.2×1011 S−1.

Influence of the Carrier Fluid Viscosity on the Rotational and Oscillatory Rheological Properties of Ferrofluids

2019 ◽  
Vol 19 (9) ◽  
pp. 5572-5581 ◽  
Author(s):  
Zhenkun Li ◽  
Decai Li ◽  
Hongchao Cui ◽  
Yanjuan Zhang ◽  
Hujun Wang
Keyword(s):  
Rheological Properties ◽  
Fluid Viscosity ◽  
Carrier Fluid

scholarly journals Ultrasonic and Heat Treatment of Crude Oils

Energies ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 3084 ◽  
Author(s):  
Aidar Kadyirov ◽  
Julia Karaeva
Keyword(s):  
Heat Treatment ◽  
Crude Oil ◽  
Rheological Properties ◽  
Experimental Method ◽  
Ultrasonic Treatment ◽  
Experimental Studies ◽  
High Viscosity ◽  
Crude Oils ◽  
Rheological Characteristics ◽  
Thermal Heating

One of the methods of influence on rheological properties of heavy high-viscosity crude oils is ultrasonic treatment. Ultrasonic treatment allows reducing the viscosity of crude oil and, therefore, reducing the costs of its production and transportation. In this paper, the influence of ultrasonic treatment on the rheological characteristics of crude oil (sample No. 1 API = 29.1, sample No. 2 API = 15.9) was investigated. An experimental method was developed. Experimental studies were carried out using the Physica MCR 102 rheometer. The influence of the intensity and duration of ultrasonic treatment on the viscosity of the initial crude oils was studied for 24 h. In addition, the rheological characteristics of the treated oil were investigated after its natural cooling to 293 K. The results are compared with similar results for thermal heating.

Effect of Shear Rate, Temperature, and Particle Concentration on the Rheological Properties of ZnO and ZrO2Nanofluids

2014 ◽  
Vol 57 (3) ◽  
pp. 489-495 ◽  
Author(s):  
A. Hernández Battez ◽  
J. L. Viesca ◽  
R. González ◽  
A. García ◽  
T. Reddyhoff ◽  
...  
Keyword(s):  
Shear Rate ◽  
Rheological Properties ◽  
Particle Concentration

THE ANALYSIS OF THE WORKING CONDITIONS OF A THRUST SQUEEZE BEARING WITH A MAGNETORHEOLOGICAL FLUID OPERATING IN THE OSCILLATORY COMPRESSION MODE

Tribologia ◽  
2019 ◽  
Vol 285 (3) ◽  
pp. 45-50
Author(s):  
Wojciech HORAK ◽  
Marcin SZCZĘCH
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Rheological Properties ◽  
Working Conditions ◽  
Axial Force ◽  
Magnetorheological Fluid ◽  
Magnetorheological Fluids ◽  
Operating Characteristics ◽  
Carrier Fluid ◽  
Load Conditions

The operating state of thrust plain bearings is a function of many parameters, both geometric and related to load conditions. Besides the methods of controlling bearings of this type used so far, new possibilities of modelling their operating characteristics by using substances with controlled rheological properties as a lubricant can be pointed out. Magnetorheological fluids create such a possibility. These are suspensions of particles with magnetic properties in a carrier fluid (usually in mineral or synthetic oil). The influence of magnetic field on this type of fluids changes their rheological properties. This process is almost instantaneous and fully reversible. The paper presents the results of investigations of a thrust squeeze bearing lubricated with magnetorheological fluid. The aim of the study was to determine the influence of selected factors on the axial force as a result of the oscillatory squeeze load.

scholarly journals The Synthesis of Organic Oils Blended Magnetorheological Fluids with the Field-Dependent Material Characterization

2019 ◽  
Vol 20 (22) ◽  
pp. 5766 ◽  
Author(s):  
Rakesh Jinaga ◽  
T. Jagadeesha ◽  
Shreedhar Kolekar ◽  
Seung-Bok Choi
Keyword(s):  
Oleic Acid ◽  
Iron Powder ◽  
Cottonseed Oil ◽  
Rheological Characteristics ◽  
Electrolytic Iron ◽  
Mr Fluid ◽  
Carrier Fluid ◽  
Silicon Oil ◽  
Field Dependent ◽  
Electrolytic Iron Powder

Automation is one of the trending terminologies in the field of engineering to achieve various sensors and actuators such as the hydraulic system. Smart fluid is also one of the hot topics for researchers to develop a type of actuator in many control systems since the fluid’s rheological characteristics can be controlled or tuned by the intensity of the external stimuli. In this work, a new smart fluid of magnetorheological (MR) fluid is proposed and its field-dependent rheological characteristics are experimentally identified. An MR fluid using the carrier fluid as the blend of three different fluids, namely silicon oil, honey, and organic oil is prepared. In addition, two types of natural oils are used, sunflower oil and cottonseed oil. The samples are prepared using the blend as the carrier fluid, electrolytic iron powder coated with guar gum as the dispersed phase, and oleic acid as an additive. The quantity of oleic acid is optimized for 30% by weight of electrolytic iron powder. Two samples based on sunflower and cottonseed oil are synthesized and characterized for shear viscosity and shear stress with respect to shear rate subjected to a variable magnetic field. The blend-based MR fluid shows about 10% improvement over the sedimentation rate of silicon oil-based MR fluid as compared to that to conventional MR fluid. The cottonseed oil blend-based MR fluid performs better than sunflower-based fluid in terms of the viscosity and structure.

Time Dependent Rheological Characteristics of Pineapple Jam

2007 ◽  
Vol 3 (3) ◽  
Author(s):  
Santanu Basu ◽  
US Shivhare ◽  
GSV Raghavan
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Rheological Properties ◽  
Time Dependent ◽  
Rheological Characteristics ◽  
Fruit Pulp ◽  
Flow Properties ◽  
Thixotropic Behavior ◽  
Dependent Flow

Jam is an intermediate moisture food containing fruit pulp, pectin, sugar and acid. The effect of sugar and pectin concentration, pH, shear rate and temperature on the time dependent rheological properties of pineapple jam was studied using a rheometer. Pineapple jam exhibited thixotropic behavior. Shear stress of the pineapple jam at a particular time of shearing depended on the shear rate, temperature and composition. Weltman, Hahn, and Figoni and Shoemaker, models were applied to describe the time dependent flow properties of pineapple jam. Hahn model described adequately the rheological characteristics of pineapple jam.

Rheological Characteristics of Ethylene Vinyl Acetate (EVA)/Silane Nanocomposites

2005 ◽  
Vol 23 ◽  
pp. 227-230 ◽  
Author(s):  
Jittiporn Kruenate ◽  
R. Tongpool ◽  
P. Kongrat
Keyword(s):  
Shear Rate ◽  
Rheological Properties ◽  
Ethylene Vinyl Acetate ◽  
High Shear Rate ◽  
Nanocomposite Films ◽  
Elastic Behaviour ◽  
Rheological Characteristics ◽  
High Shear ◽  
Steady Mode ◽  
Polymer Strength

EVA/tetraethylorthosilane(silane) nanocomposites were prepared. Rheological properties were studied in both dynamic and steady modes at 150oC. The rheological properties of the nanocomposites are strongly affected by silane dispersed in EVA matrix. As silane content incresed, the polymer strength increased due to interconnections between filler clusters which can be disrupted by high shear rate (in steady mode). The degree of silane dispersion in the EVA matrix decreased with increasing silane content, leading to a “pseudo-solid-like” behaviour. The samples showed viscous and elastic behaviour at low- and high-shear rate regions, respectively. The nanocomposite films were almost as clear as EVA film.

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