The Research of Capacitance Characteristics of MRF

2012 ◽  
Vol 246-247 ◽  
pp. 1096-1101
Author(s):  
Song Wang ◽  
Guo Tian He ◽  
Li Song ◽  
Ze Yu Xu ◽  
Ying Chun Ran
Keyword(s):  
Magnetic Field ◽  
Dielectric Constant ◽  
Electrical Characteristics ◽  
Field Change ◽  
Aircraft Manufacturing ◽  
Magnetic Field Change ◽  
Capacitance Characteristics ◽  
Magneto Rheological ◽  
Magnetic Induction Intensity ◽  
The Magnetic Field

With the development of theory that research on Magneto-Rheological Fluids (MRF), the MRF have been used in many fields in our life. The electrical characteristics of MRF can be widely used in automatic control, medical, automotive, aircraft manufacturing and many other areas .Firstly, this article have derived the formula of MRF between capacitance and Dielectric constant, made the Capacitors which can load the MRF. And then we measure the change of capacitance which is filled with the MRF when the time of magnetic field change, And we also measure the sensitivity of the dielectric constant of different concentrations of MRF as the magnetic field changes. And at last, we have made the curve of the capacitance - magnetic induction intensity the experimental results have been analyzed. We have the conclusion that when the magnetic field increases, the dielectric constant is also increases, resulting in increased capacitance of the conclusions of MRF. Introduction

Magnetocaloric Effect in Ni-Mn-Ga and Ni-Co-Mn-In Heusler Alloys

2009 ◽  
Vol 1200 ◽  
Author(s):  
Vasiliy Buchelnikov ◽  
Sergey Taskaev ◽  
Mikhail Drobosyuk ◽  
Vladimir Sokolovskiy ◽  
Viktor Koledov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetocaloric Effect ◽  
Curie Point ◽  
Direct Method ◽  
Heusler Alloys ◽  
Field Change ◽  
Adiabatic Temperature Change ◽  
Magnetic Field Change ◽  
A Direct Method ◽  
The Magnetic Field

AbstractThe positive magnetocaloric effect (MCE) in the vicinity of the Curie point in Ni2+xMn1-xGa (x=0.33, 0.36, 0.39) Heusler alloys and the negative and positive MCE near the metamagnetostructural (MMS) transition and the Curie point, respectively, in Ni45Co5Mn36.5In13.5 Heusler alloy has been measured by a direct method. For the magnetic field change ΔH = 2 T, the maximal adiabatic temperature change ΔTad at the Curie point in Ni2+xMn1-xGa alloys is larger than 0.6 K. For Ni45Co5Mn36.5In13.5 alloy, the maximal value of ΔTad = 1.68 K (for the same magnetic field change, ΔH = 2 T) is observed at the MMS phase transition temperature.

The Magnetocaloric Effect in Ni-Mn-X (X=Ga, in) Heusler Alloys and Manganites with Magnetic Transition close to Room Temperature

2010 ◽  
Vol 168-169 ◽  
pp. 165-168
Author(s):  
Vasiliy D. Buchelnikov ◽  
Mikhail Drobosyuk ◽  
E.A. Smyshlyaev ◽  
O.O. Pavlukhina ◽  
A.V. Andreevskikh ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetocaloric Effect ◽  
Room Temperature ◽  
Direct Method ◽  
Magnetic Transition ◽  
Heusler Alloys ◽  
Field Change ◽  
Adiabatic Temperature Change ◽  
Magnetic Field Change ◽  
The Magnetic Field

The magnetocaloric effect (MCE) in theNi2+xMn1-xGa (x = 0.33, 0.36, 0.39), Ni50Mn25In25, Ni54Mn21Ga18In7, Ni53.5Mn21.5Ga16In9, Ni45Co5Mn36.5In13.5 Heusler alloys and in the La0.7BayCa0.3-yMnO3 (y = 0.12, 0.24, 0.3) manganites at the Curie points have been measured by the direct method. For the magnetic field change H = 2 T, the maximal adiabatic temperature change Tad in the Ni2+xMn1-xGa alloys is larger than 0.6 K. For the Ni50Mn25In25 alloy the maximal value of Tad = 1.51 K (for the same magnetic field change H = 2 T) is observed at the magnetic phase transition temperature.

scholarly journals The magnetic field change associated with the very close lightning ground discharge struck to an electric power trasmission line.

1993 ◽  
Vol 13 (2) ◽  
pp. 145-150
Author(s):  
Nobuyuki Takagi ◽  
Tomoyasu Sugiura ◽  
Teiji Watanabe ◽  
Izumi Arima ◽  
Tosio Takeuti ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electric Power ◽  
Field Change ◽  
Magnetic Field Change ◽  
The Magnetic Field

Measurement of the magnetic field change in a pulsed high current magnetron discharge

2004 ◽  
Vol 13 (4) ◽  
pp. 654-661 ◽  
Author(s):  
Johan Bohlmark ◽  
Ulf Helmersson ◽  
Michael VanZeeland ◽  
I Axnäs ◽  
Jones Alami ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Current ◽  
Field Change ◽  
Magnetron Discharge ◽  
Magnetic Field Change ◽  
The Magnetic Field

Direct and Inverse Magnetocaloric Effect in Ni1.81Mn1.64In0.55 Multifunctional Heusler Alloy

2015 ◽  
Vol 233-234 ◽  
pp. 183-186 ◽  
Author(s):  
Rafael Fayzullin ◽  
Vasiliy D. Buchelnikov ◽  
Mikhail Drobosyuk ◽  
Alexey Mashirov ◽  
Alexander Kamantsev ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
Magnetocaloric Effect ◽  
Heusler Alloy ◽  
Direct Method ◽  
Field Change ◽  
Adiabatic Temperature Change ◽  
Phase Transition Temperatures ◽  
Magnetic Field Change ◽  
The Magnetic Field

The magnetocaloric effect (MCE) in Ni1.81Mn1.64In0.55 Heusler alloy has been measured by the direct method. The field dependences of the magnetization were obtained. The phase transition temperatures were determined. The maximal adiabatic temperature change ΔTad near the Curie temperature is 1.8 K under the magnetic field change ∆H = 18 kOe. The inverse MCE (∆Tad = -3.72 K) in the same field change takes place near the temperature of martensitic transformation.

scholarly journals Reversibility of the Magnetocaloric Effect in the Bean-Rodbell Model

2021 ◽  
Vol 7 (5) ◽  
pp. 60
Author(s):  
Luis M. Moreno-Ramírez ◽  
Victorino Franco
Keyword(s):  
Magnetic Field ◽  
Thermal Hysteresis ◽  
Entropy Change ◽  
Second Order ◽  
Zero Field ◽  
First Order ◽  
Magnetic Field Change ◽  
Magnetocaloric Materials ◽  
Moderate Magnetic Field ◽  
The Magnetic Field

The applicability of magnetocaloric materials is limited by irreversibility. In this work, we evaluate the reversible magnetocaloric response associated with magnetoelastic transitions in the framework of the Bean-Rodbell model. This model allows the description of both second- and first-order magnetoelastic transitions by the modification of the η parameter (η<1 for second-order and η>1 for first-order ones). The response is quantified via the Temperature-averaged Entropy Change (TEC), which has been shown to be an easy and effective figure of merit for magnetocaloric materials. A strong magnetic field dependence of TEC is found for first-order transitions, having a significant increase when the magnetic field is large enough to overcome the thermal hysteresis of the material observed at zero field. This field value, as well as the magnetic field evolution of the transition temperature, strongly depend on the atomic magnetic moment of the material. For a moderate magnetic field change of 2 T, first-order transitions with η≈1.3−1.8 have better TEC than those corresponding to stronger first-order transitions and even second-order ones.

In Search of the Jerk Element

2021 ◽  
Author(s):  
Zachary P. Belyaev ◽  
Samuel N. Downes ◽  
Philip A. Voglewede
Keyword(s):  
Magnetic Field ◽  
Motion Planning ◽  
System Performance ◽  
Theoretical Background ◽  
Physical Parameters ◽  
Common Elements ◽  
Planning And Control ◽  
Magneto Rheological ◽  
And Control ◽  
The Magnetic Field

Abstract Mechanical components, such as springs, dampers and mass, alter and influence an engineered system’s motion based upon a system’s position, velocity and acceleration, respectively. This paper aims to discover and develop another element (dubbed the damper) which provides a force proportional to a system’s jerk (i.e., the derivative of acceleration) to better engineer a system’s response. By utilizing the known applications of jerk in motion planning and control theory, existing possible physical implementations and uses of jerk and the jerk element are discussed in relation to its influence on the system’s response, specifically vibration. Using a Buckingham Pi approach, the theoretical background of the jerk element is presented and possible physical parameters are combined to show how the jerk element could be created from common elements and parameters. The most promising approach of varying the magnetic field of existing magneto-rheological dampers is developed to give an example of the jerk element along with the difficulties and concerns in developing the jerk element. This paper serves less of a purpose towards answering all questions of the jerk element, but rather focuses more on posing the appropriate questions which sets the stage for an easily realizable future jerk element which can improve system performance.

Characteristics of Magneto-Rheological Elastomer under Stick-Slip Condition

2020 ◽  
Vol 842 ◽  
pp. 193-198
Author(s):  
Kwang Hee Lee ◽  
Chul Hee Lee
Keyword(s):  
Magnetic Field ◽  
Glass Plate ◽  
Static Friction ◽  
Low Noise ◽  
Friction Behavior ◽  
Stick Slip ◽  
The Difference ◽  
Magneto Rheological ◽  
Squeal Noise ◽  
The Magnetic Field

This paper examines the characteristics of stick-slip phenomena between the glass plate and Magneto-Rheological Elastomer (MRE) surface. Stick-slip phenomena are the spontaneous jerking motion that occurs while two objects are sliding over each other, usually accompanied by noise. Stick-slip is generated when it involves discontinuous frictional degradation when moving from static friction to dynamic friction. The phenomena can lead to uneven wear patterns, vibration and squeal noise which cause a shorter lifespan for the corresponding mechanical elements. MREs are kind of function materials to consist of a polymeric matrix with embedded ferromagnetic particles. Mechanical properties of the MREs can be controlled by the application of magnetic fields. The magnetic field-based controllability can be applied to the control of stick-slip phenomena. The friction experiment is conducted with the Reciprocating Friction Tester (RFT). The sliding speed of the RFT should be in low-speed conditions in order to make the stick-slips relatively easy to occur. A uniform magnetic field and a weight load are applied to the MRE sample to observe the effect of various experimental parameters on the movement of the stick-slip. In addition, frictional sounds due to the stick-slip phenomenon under different loads and magnetic field strength are measured and analyzed. The results of this experiment show that as the strength of the magnetic field increases, the difference in stiffness between the wipers-glass decreases, mitigating fricatives. The result is expected to be well applied to low-noise automotive wipers based on the controllability of friction behavior and squeal noise.

scholarly journals Numerical Simulation on the Brake Effect of FAC-EMBr and EMBrRuler in the Continuous Casting Mold

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1620
Author(s):  
Zhuang Li ◽  
Lintao Zhang ◽  
Yanming Bao ◽  
Danzhu Ma
Keyword(s):  
Magnetic Field ◽  
Molten Steel ◽  
Casting Speed ◽  
Submerged Entry Nozzle ◽  
Pole Position ◽  
Level Fluctuation ◽  
Steel Flow ◽  
Magnetic Poles ◽  
Magnetic Induction Intensity ◽  
The Magnetic Field

The brake effect of the freestanding adjustable combination electromagnetic brake (FAC-EMBr) and EMBr ruler on the behavior of molten steel flow and the level fluctuation were investigated with the numerical method. The effects of the horizontal magnetic pole position (EMBr ruler), magnetic induction intensity, and casting speed on two types of electromagnetic brakes were studied. The numerical simulation results show that the magnetic field caused by the EMBr ruler is mainly distributed under the submerged entry nozzle (SEN), and it is very weak nearby the meniscus area. After the FAC-EMBr is applied, the magnetic field is mainly distributed in the area below the submerged entry nozzle, the upper roll region, and in the meniscus region. The application of the electromagnetic brake can effectively suppress the impact of the jet and decrease the molten steel velocity in the meniscus area. The brake effect of the EMBr ruler on the behavior of the molten steel flow and the level fluctuation is significantly influenced by the horizontal magnetic pole position. The increasing of the magnetic flux density can significantly increase the velocity of molten steel in the upper roll region and lead to an intense fluctuation in the steel/slag interface, as the horizontal magnetic field cannot cover the three key regions. The brake effect of the FAC-EMBr is less influenced by the variation of the process parameters due to the addition of vertical magnetic poles. Additionally, the “secondary braking effect” of the vertical magnetic poles can help to lower the increase of velocity in the upper roll region caused by the excessive magnetic induction intensity and the high casting speed. Therefore, even under the high casting speed conditions, the application of a new type of FAC-EMBr is also an efficient way to suppress the molten steel flow and level fluctuation at the meniscus area and decrease the possibility of slag entrapment.

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