scholarly journals Enhancement of Particle Alignment Using Silicone Oil Plasticizer and Its Effects on the Field-Dependent Properties of Magnetorheological Elastomers

2019 ◽  
Vol 20 (17) ◽  
pp. 4085 ◽  
Author(s):  
Khairi ◽  
Fatah ◽  
Mazlan ◽  
Ubaidillah ◽  
Nordin ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Flux ◽  
Closed Loop ◽  
Silicone Oil ◽  
Dynamic Properties ◽  
Field Dependent ◽  
The Matrix ◽  
Industry Applications ◽  
Particle Alignment ◽  
Strain Sweep

The existing mold concept of fabricating magnetorheological elastomer (MRE) tends to encounter several flux issues due to magnetic flux losses inside the chamber. Therefore, this paper presents a new approach for enhancing particle alignment through MRE fabrication as a means to provide better rheological properties. A closed-loop mold, which is essentially a fully guided magnetic field inside the chamber, was designed in order to strengthen the magnetic flux during the curing process with the help of silicone oil (SO) plasticizers. The oil serves the purpose of softening the matrix. Scanning electron microscopy (SEM) was used to observe the surface morphology of the fabricated MRE samples. The field-dependent dynamic properties of the MREs were measured several ways using a rheometer, namely, strain sweep, frequency sweep, and magnetic field sweep. The analysis implied that the effectiveness of the MRE was associated with the use of the SO, and the closed-loop mold helped enhance the absolute modulus up to 0.8 MPa. The relative magnetorheological (MR) effects exhibited high values up to 646%. The high modulus properties offered by the MRE with SO are believed to be potentially useful in industry applications, particularly as vibration absorbers, which require a high range of stiffness.

scholarly journals Effect of Mould Orientation on the Field-Dependent Properties of MR Elastomers under Shear Deformation

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3273
Author(s):  
Muntaz Hana Ahmad Khairi ◽  
Saiful Amri Mazlan ◽  
Ubaidillah ◽  
Nur Azmah Nordin ◽  
Siti Aishah Abdul Aziz ◽  
...  
Keyword(s):  
Magnetic Flux ◽  
Shear Deformation ◽  
Silicone Oil ◽  
Dynamic Properties ◽  
Industrial Applications ◽  
Shear Direction ◽  
Air Gaps ◽  
Field Dependent ◽  
Pass Through ◽  
Mr Effect

In this study, magnetorheological elastomer (MRE) was fabricated using an electromagnetic device with a new configuration mold at the orientation of 0°, 45° and 90°. This new curing concept enhanced the alignment of carbonyl iron particles (CIPs) within the silicone matrix in the presence of silicone oil (SO) during solidifying, by eliminating air gaps to prevent magnetic flux losses. Using a mold made of steel, which is a magnetic material, the mold functions as a guide for concentrated magnetic flux of 0.315 T to pass through the MRE sample. Scanning electron microscopy (SEM) was used to observe the surface morphology of the fabricated MRE samples particularly the alignment of the CIPs. The field-dependent dynamic properties of the MREs were measured using a rheometer. The analysis implied that the effectiveness of the MRE operating under shear deformation with this curing concept provided the highest magneto-induced modulus of 1.01 MPa when a 45° orientation mold is used, with relative magnetorheological (MR) effect value up to 918%, followed by 0° mold orientation with 0.79 MPa magneto-induced modulus and 646% relative MR effect. The high modulus properties offered by this MRE are believed to be potentially useful in industrial applications where a high range of stiffness is required particularly in the shear direction.

Simulation and Validation of an Anisotropic Magnetorheological Elastomers Mold with Various Alignment Angles

2018 ◽  
Vol 772 ◽  
pp. 66-70
Author(s):  
Ilham Bagus Wiranto ◽  
Ubaidillah ◽  
Dody Ariawan ◽  
Faishal Harish ◽  
Saiful Amri Mazlan ◽  
...  
Keyword(s):  
Magnetic Flux ◽  
Flux Density ◽  
Magnetic Flux Density ◽  
Mold Design ◽  
Magnetorheological Elastomers ◽  
Density Prediction ◽  
Best Value ◽  
The Matrix ◽  
Particle Alignment ◽  
The Difference

In this study, anisotropic magnetorheological elastomers (MREs) mold design with capability of aligning the filler in several angles (0 ̊, 45 ̊, and 90 ̊) were developed. The mold was equipped with electromagnet coil to generate the magnetic flux. The distribution of magnetic flux density in the mold and inside the chamber was investigated by using finite element magnetic analysis. Magnetic flux density of 0.3 T was considered best value to form good particle alignment in the matrix. Moreover, the mold design was fabricated using same material as in the simulation. The magnetic flux density was taken at casing wall and measured by gauss-meter. The data was compared with simulation results. The differences between experimental and simulation is in the range of 6-40 mT. Since the difference is insignificant, it can be said that the data is valid. Finally, the model can be used for further magnetic flux density prediction inside the chamber. In the simulation, it was found that the current needed to generate at least 0.3 T inside the chamber for 0 ̊, 45 ̊, and 90 ̊ are 0.2A, 0.1A, and 3A, respectively.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

MAGNETIC FIELD DEPENDENT RESTSTRAHLEN SPECTRA IN PARAMAGNETIC CeF3

1981 ◽  
Vol 42 (C6) ◽  
pp. C6-499-C6-501 ◽  
Author(s):  
H. Gerlinger ◽  
G. Schaack
Keyword(s):  
Magnetic Field ◽  
Field Dependent

MAGNETIC FIELD DEPENDENT RELAXATION TIME IN p-InSb AT LOW TEMPERATURES

1981 ◽  
Vol 42 (C5) ◽  
pp. C5-689-C5-693
Author(s):  
J. D.N. Cheeke ◽  
G. Madore ◽  
A. Hikata
Keyword(s):  
Magnetic Field ◽  
Relaxation Time ◽  
Low Temperatures ◽  
Field Dependent

METHOD OF SYNTHESIS OF CLOSED-LOOP SYSTEMS OF ACTIVE SHIELDING MAGNETIC FIELD OF POWER TRANSMISSION LINES

2016 ◽  
Vol 2016 (4) ◽  
pp. 8-10 ◽  
Author(s):  
B.I. Kuznetsov ◽  
◽  
A.N. Turenko ◽  
T.B. Nikitina ◽  
A.V. Voloshko ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Transmission Lines ◽  
Closed Loop ◽  
Power Transmission ◽  
Power Transmission Lines ◽  
Closed Loop Systems ◽  
Active Shielding

Basic Statements of Research and Magnetic Field of Axial Excitation Inductor Generator

2011 ◽  
Vol 28 (1) ◽  
pp. 49-52
Author(s):  
Igors Stroganovs ◽  
Andrejs Zviedris
Keyword(s):  
Magnetic Field ◽  
Finite Element Method ◽  
Finite Element ◽  
Magnetic Flux ◽  
Magnetic System ◽  
System Optimization ◽  
Magnetic Saturation ◽  
The Finite Element Method ◽  
Flux Linkage ◽  
Axial Excitation

Basic Statements of Research and Magnetic Field of Axial Excitation Inductor GeneratorIn this work the main features of axial excitation inductor generators are described. Mathematical simulation of a magnetic field is realized by using the finite element method. The objective of this work is to elucidate how single elements shape, geometric dimensions and magnetic saturation of magnetic system affect the main characteristics of the field (magnetic induction, magnetic flux linkage). The main directions of a magnetic system optimization are specified.

A simulation apparatus for the experimental study of batch reactor control methods

1986 ◽  
Vol 51 (6) ◽  
pp. 1259-1267
Author(s):  
Josef Horák ◽  
Petr Beránek
Keyword(s):  
Experimental Study ◽  
Closed Loop ◽  
Dynamic Properties ◽  
Batch Reactor ◽  
Exothermic Reaction ◽  
Electric Heating ◽  
Batch Reactors ◽  
Exchange Area ◽  
The Stability ◽  
Methods Of Control

A simulation apparatus for the experimental study of the methods of control of batch reactors is devised. In this apparatus, the production of heat by an exothermic reaction is replaced by electric heating controlled by a computer in a closed loop; the reactor is cooled with an external cooler whose dynamic properties can be varied while keeping the heat exchange area constant. The effect of the cooler geometry on its dynamic properties is investigated and the effect of the cooler inertia on the stability and safety of the on-off temperature control in the unstable pseudostationary state is examined.

scholarly journals Energetics of magnetic transients in a solar active region plage

2019 ◽  
Vol 623 ◽  
pp. A176 ◽  
Author(s):  
L. P. Chitta ◽  
A. R. C. Sukarmadji ◽  
L. Rouppe van der Voort ◽  
H. Peter
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Magnetic Flux ◽  
Numerical Simulations ◽  
Extreme Ultraviolet ◽  
Spatial Scales ◽  
Coronal Loops ◽  
The Sun ◽  
Flux Emergence ◽  
Transient Events

Context. Densely packed coronal loops are rooted in photospheric plages in the vicinity of active regions on the Sun. The photospheric magnetic features underlying these plage areas are patches of mostly unidirectional magnetic field extending several arcsec on the solar surface. Aims. We aim to explore the transient nature of the magnetic field, its mixed-polarity characteristics, and the associated energetics in the active region plage using high spatial resolution observations and numerical simulations. Methods. We used photospheric Fe I 6173 Å spectropolarimetric observations of a decaying active region obtained from the Swedish 1-m Solar Telescope (SST). These data were inverted to retrieve the photospheric magnetic field underlying the plage as identified in the extreme-ultraviolet emission maps obtained from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). To obtain better insight into the evolution of extended unidirectional magnetic field patches on the Sun, we performed 3D radiation magnetohydrodynamic simulations of magnetoconvection using the MURaM code. Results. The observations show transient magnetic flux emergence and cancellation events within the extended predominantly unipolar patch on timescales of a few 100 s and on spatial scales comparable to granules. These transient events occur at the footpoints of active region plage loops. In one case the coronal response at the footpoints of these loops is clearly associated with the underlying transient. The numerical simulations also reveal similar magnetic flux emergence and cancellation events that extend to even smaller spatial and temporal scales. Individual simulated transient events transfer an energy flux in excess of 1 MW m−2 through the photosphere. Conclusions. We suggest that the magnetic transients could play an important role in the energetics of active region plage. Both in observations and simulations, the opposite-polarity magnetic field brought up by transient flux emergence cancels with the surrounding plage field. Magnetic reconnection associated with such transient events likely conduits magnetic energy to power the overlying chromosphere and coronal loops.

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