Формирование изображений электрических сигналов преобразователя магнитного поля при гистерезисной интерференции для контроля металлов в импульсных магнитных полях

2020 ◽  
pp. 38-45
Author(s):  
В.В. Павлюченко ◽  
Е.С. Дорошевич
Keyword(s):  
Magnetic Field ◽  
Aluminum Plate ◽  
Thickness Variation ◽  
Magnetic Carrier ◽  
Electric Voltage ◽  
Total Strength ◽  
Magnetic Field Transducer ◽  
The Given ◽  
The Magnetic Field

Based on the developed methods of hysteresis interference, the calculated dependences U(x) of the electric voltage taken from the magnetic field transducer on the x coordinate were obtained. A magnetic carrier with an arctangent characteristic was exposed to a series of bipolar pulses of the magnetic field of a linear inductor of one, two, three, four, five and fifteen pulses. An algorithm is presented for the sequence of changes in the magnitude of the total strength of the magnetic field pulses on the surface of an aluminum plate, which provides the same amplitude of hysteresis oscillations of the electric voltage and makes it possible to obtain a linear difference dependence U(x) for wedge-shaped and flat aluminum samples. The results obtained make it possible to increase the accuracy and efficiency of control of the thickness of the object and its thickness variation in the given directions, as well as the defects of the object.

DETECTION OF INTEGRITY DEFECTS IN ALUMINUM SPECIMENS BY THE MAGNETIC PULSE METHOD

2019 ◽  
Vol 85 (4) ◽  
pp. 28-32
Author(s):  
Vladimir V. Pavlyuchenko ◽  
Elena S. Doroshevich
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Pulse Method ◽  
Magnetic Pulse ◽  
Magnetic Field Direction ◽  
Magnetic Carrier ◽  
Electric Voltage ◽  
Useful Signal ◽  
Measurement Plane ◽  
Aluminum Plates

Experimental time dependences of the electric voltage U(t), taken from the induction magnetic head when scanning it with a magnetic carrier with magnetic field records of artificial defects of the integrity (slits) with a width of (1.0 - 10.0) x 10-5  m in aluminum plates from 1.5 x 10-6 to 2.0 x 10-3 m are presented. On the magnetic carrier the magnetic fields of the defects that occur when aluminum plates are exposed to a pulse of magnetic field of plane inductor (action time of about 1.0 x 10-4 sec). Dependences of U(t) for different depths of bedding of the defects and thickness of the layer of the material above them in the specified ranges of influences are obtained. In this case, distributions of instantaneous magnetic fields are recorded on the surface area of objects of the order of 1.0 x 10-3 m2 with a resolution in the measurement plane of 1.0 x 10-8 m2. The novelty of the method consists in determination of the amplitude of the main pulse of the field and build up time, the shape of the leading and trailing edges, as well as the amplitude, build up time, the number and polarity of the outliers of magnetic field, direction of the applied field, operations of smoothing, calculation, separation of the useful signal and operations of recognition of the defect information recorded on the magnetic medium with analysis of the dependences U(t). The developed method for controlling objects from electrically conductive materials makes it possible to increase several times the accuracy and speed of the control of the integrity defects in diamagnetic and paramagnetic metals.

The Simulation of Lane Based on Magnetic Markers Guidance in Laboratory

2013 ◽  
Vol 823 ◽  
pp. 370-373
Author(s):  
Wei Wang
Keyword(s):  
Magnetic Field ◽  
Power Amplifier ◽  
Field Intensity ◽  
Direct Current ◽  
Magnetic Field Intensity ◽  
Single Chip ◽  
Single Chip Microcomputer ◽  
Electric Voltage ◽  
Magnetic Markers ◽  
The Magnetic Field

It is a high expense that the experiment of the testing vehicle based on magnetic markers carrying on outdoors. The distribution and movement of magnetic markers were simulated by direct-current electromagnet, using single chip microcomputer and power amplifier to control direct-current electromagnet. It cuts down the expense of experiment. This dissertation is focus on mainly the design of lane simulator. In the lane simulator, every 0.5m arranged a direct-current electromagnet. When the speed is 80km/h,the electrifying time of the direct-current electromagnet is 0.025s. And the electric voltage of the direct-current electromagnet is 24v, and the magnetic field intensity of the direct-current electromagnet is 12000Gs.

scholarly journals Modulation frequency and velocity variation of ions in a magnetized plasma sheath for different obliqueness of the field

BIBECHANA ◽  
2021 ◽  
Vol 18 (1) ◽  
pp. 134-139
Author(s):  
Bhesha Raj Adhikari ◽  
Hari Prasad Lamichhane ◽  
Raju Khanal
Keyword(s):  
Magnetic Field ◽  
Modulation Frequency ◽  
Maximum Amplitude ◽  
Plasma Sheath ◽  
Magnetized Plasma ◽  
Velocity Variation ◽  
Damping Factor ◽  
Force Equation ◽  
The Given ◽  
The Magnetic Field

The understanding of ion dynamics in magnetized plasma sheath is crucial for all applications of plasma. The velocity variation as well as modulation frequency of ions in a magnetized plasma sheath has been studied for different obliqueness of the magnetic field. The governing Lorentz force equation has been solved numerically for the given boundary conditions as applicable in the kinetic simulation of the sheath. For different obliqueness of the magnetic field, the average values, maximum amplitude, damping factor as well as frequency of oscillation are studied. The oscillating velocity components change at different rates depending on their orientation with respect to the field direction. Significant changes in the damping factor and modulation frequency has been observed for all components of velocity; however, the frequency of oscillation remains the same. As the obliqueness increases, shoulder natures in the components of velocity are observed. BIBECHANA 18 (2021) 134-139

scholarly journals Effects of thermal stress, magnetic field and rotation on the dispersion of elastic waves in an inhomogeneous five-layered plate with alternating components

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042094046
Author(s):  
Rahmatullah Ibrahim Nuruddeen ◽  
Rab Nawaz ◽  
Qazi Muhammad Zaigham Zia
Keyword(s):  
Magnetic Field ◽  
Thermal Stress ◽  
Differential Equations ◽  
Classical Method ◽  
Harmonic Wave ◽  
External Effects ◽  
Stress Rotation ◽  
Mathematica Software ◽  
The Given ◽  
The Magnetic Field

This study explores the effects of the thermal stress, rotation, and magnetic fields on the propagation of surface waves in a symmetric five-layered inhomogeneous elastic plate. The harmonic wave solution was adopted to reduce the given partial differential equations to their corresponding ordinary differential equations, which were later solved using a classical method. The Mathematica software was also employed for the numerical simulations. The dispersion relations associated with both the symmetric and antisymmetric modes have been determined and analyzed with regard to the aforementioned external effects and rotation. The variations in thermal stress positively affect the wave propagation in the plate even for relatively smaller values of the temperature variation. Also, the same trend is observed in the case of the magnetic field, but for higher values. Finally, for the rotation, it was found that the angular velocity must reach at least 104 before a significant change is observed; which in fact differs from the situations of half-plane reflection and single-layered.

Axialsymmetrische Lösungen der magnetohydrostatischen Gleichung mit Oberflächenströmen

1957 ◽  
Vol 12 (10) ◽  
pp. 826-832
Author(s):  
L. Biermann ◽  
K. Hain ◽  
K. Jörgens ◽  
R. Lust
Keyword(s):  
Magnetic Field ◽  
Boundary Conditions ◽  
Axial Symmetry ◽  
Circular Cross Section ◽  
Homogeneous Field ◽  
Electric Currents ◽  
Azimuthal Component ◽  
Axis Of Symmetry ◽  
The Given ◽  
The Magnetic Field

Es werden axialsymmetrische Lösungen der magnetohydrostatischen Gleichung betrachtet, bei denen das Gas einen Torus erfüllt, dessen Querschnitt im allgemeinen kreisförmig angenommen wird. Zur Vereinfachung wird angenommen, daß die elektrischen Ströme nur an der Oberfläche fließen. Für den Fall, daß diese Ströme gegeben sind, wird ein Verfahren angegeben, mit dem das äußere Magnetfeld berechnet werden kann, welches zusammen mit dem durch den gegebenen Strom erzeugten Feld die Grenzbedingungen erfüllt. Dies Verfahren wird für den Fall rein azimutaler Ströme mit einer Näherungsmethode und dann exakt durchgeführt. In erster Näherung genügt die Überlagerung eines homogenen Feldes parallel zur Symmetrieachse des Torus. Für den Fall gegebener meridionaler Ströme zeigt sich, daß die Randbedingungen nur durch Überlagerung eines zusätzlichen azimutalen Stromes erfüllbar sind, zusammen mit einem geeigneten meridionalen äußeren Magnetfeld. Im axialsymmetrischen Fall ist also stets mindestens eine azimutale Stromkomponente erforderlich.It is proposed to consider solutions of the magnetohydrostatic equation of axial symmetry in which the plasma is contained in a torus with circular cross-section. For mathematical simplification it is furthermore assumed, that the electric currents flow exclusively at the surface of the plasma. For the case, that these currents are assumed to be given, a method is outlined by which it is possible to calculate the exterior magnetic field which together with the magnetic field produced by the given currents, satisfies the boundary conditions at the surface. This procedure is carried through for the case of purely azimuthal electric currents, first by an approximate method, then by an exact method. To a first approximation it is sufficient to superpose an homogeneous field parallel to the axis of symmetry. For the case that the given currents are in a meridional planes, it is seen, that the boundary conditions can be satisfied only by the superposition of an additional current together with a suitable meridional exterior magnetic field. Therefore in the case of axial symmetry at least one azimuthal component of the electric current is necessary.

Observing the galactic magnetic field

1967 ◽  
Vol 31 ◽  
pp. 375-380
Author(s):  
H. C. van de Hulst
Keyword(s):  
Magnetic Field ◽  
Fair Agreement ◽  
Solar Neighbourhood ◽  
Galactic Magnetic Field ◽  
The Magnetic Field

Various methods of observing the galactic magnetic field are reviewed, and their results summarized. There is fair agreement about the direction of the magnetic field in the solar neighbourhood:l= 50° to 80°; the strength of the field in the disk is of the order of 10-5gauss.

Evolution of Large-Scale Coronal Structures

1994 ◽  
Vol 144 ◽  
pp. 29-33
Author(s):  
P. Ambrož
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Large Scale ◽  
Coronal Magnetic Field ◽  
Source Surface ◽  
Solar Cycles ◽  
Characteristic Relationship ◽  
The Magnetic Field ◽  
Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

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.

On the Configuration of the Magnetic Field of β CrB

1976 ◽  
Vol 32 ◽  
pp. 613-622
Author(s):  
I.A. Aslanov ◽  
Yu.S. Rustamov
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Radial Velocity ◽  
Magnetic Field Strength ◽  
Complex Shape ◽  
Rotation Period ◽  
Field Variation ◽  
Magnetic Field Variation ◽  
Secular Variations ◽  
The Magnetic Field

SummaryMeasurements of the radial velocities and magnetic field strength of β CrB were carried out. It is shown that there is a variability with the rotation period different for various elements. The curve of the magnetic field variation measured from lines of 5 different elements: FeI, CrI, CrII, TiII, ScII and CaI has a complex shape specific for each element. This may be due to the presence of magnetic spots on the stellar surface. A comparison with the radial velocity curves suggests the presence of a least 4 spots of Ti and Cr coinciding with magnetic spots. A change of the magnetic field with optical depth is shown. The curve of the Heffvariation with the rotation period is given. A possibility of secular variations of the magnetic field is shown.

Materials for Electron Beam Information Storage

1969 ◽  
Vol 27 ◽  
pp. 152-153 ◽  
Author(s):  
D. E. Speliotis
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Recent Literature ◽  
Electron Beams ◽  
Information Storage ◽  
The Subject ◽  
The Magnetic Field

The interaction of electron beams with a large variety of materials for information storage has been the subject of numerous proposals and studies in the recent literature. The materials range from photographic to thermoplastic and magnetic, and the interactions with the electron beam for writing and reading the information utilize the energy, or the current, or even the magnetic field associated with the electron beam.

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