Ampere Force Research Articles

Experimental studies of the magnetic structure and plasma dynamics in current sheets (a review)

Based on measurements of magnetic fields in current sheets, spatial distributions of the electric current and electrodynamic forces in successive stages of the sheet evolution are determined. Two new effects manifesting themselves mostly in the late stages of the current sheet evolution have been discovered, namely, expansion of the current flow region at the periphery of the sheet and the appearance of a region with inverse currents, which gradually expands from the periphery toward the center of the sheet. Using spectroscopic methods, generation of superthermal plasma flows accelerated along the sheet width from the center toward the periphery has been revealed and investigated. The measured energies of accelerated plasma ions satisfactorily agree with the Ampere forces determined from magnetic measurements. The excitation of inverse currents additionally confirms the motion of high-speed plasma flows from the center of the current sheet toward its side edges.

Experimental Study on Deflection Behavior of Vacuum Arcs Under the Influence of External Transverse Magnetic Field

In real power system, when the three-phase short-circuit fault occurs, the vacuum arc in one phase will be influenced by the transverse magnetic field generated by neighbor phases and bus bars. This kind of effect is the main cause of the unstable arc and deflected erosion of contact plates, which leads to the failure of vacuum circuit breakers interruption. The objective of this paper is to get more insight into the influence of external transverse magnetic field (ETMF) on vacuum arc’s behavior. The experiments were conducted in a demountable vacuum chamber with pressure about $10^{-4}$ Pa. The cup-type axial magnetic field contacts were used, whose material was pure copper and the diameter is 35 mm. The uniform ETMF in the arc region was generated by two parallel bulk permanent magnets. The experiments were conducted under different ETMFs (0, 15, and 25 mT) and current levels (1-, 2.5-, and 4-kA rms) with different gap distances (6, 8.5, and 11 mm). The videos of arc column were recorded by a high-speed charge-coupled device camera. Under the action of ETMF, the vacuum arc got deflected. Due to the retrograde motion of cathode spots and Ampere force acting on arc column, the deflection behaviors during three typical periods (that is, initial, peak value, and close-to-current-zero period) were different. Moreover, the deflection level of vacuum arc at current peak value moment was greatly impacted by ETMF and gap distance. Larger the ETMF and gap distance were, higher the deflection level at current peak value moment was. The simulation results of arc deflection based on magnetic-hydrodynamic model were in agreement with experimental results in trends.

Experimental Investigation of Separated Shear Flow under Subharmonic Perturbations over a Backward-Facing Step

Subharmonic-perturbed shear flow downstream of a two-dimensional backward-facing step was experimentally investigated. The Reynolds number was Reh = 2.0 ×104, based on free-stream velocity and step height. Planar 2D-2C particle image velocimetry was employed to measure the separating and reattaching flow in the horizontal-vertical plane in the center position. The subharmonic perturbations were generated by an oscillating flap which was implemented over the step edge and driven by periodic Ampere force. The subharmonic frequency was 55 Hz as the half of the fundamental frequency of the turbulent shear layer. As a result of the subharmonic perturbations, the size of recirculation region behind the backward-facing step is reduced and the time-averaged reattachment length is 31.0% shorter than that of the natural flow. The evolution of vortices, including vortex roll-up, growth and breakdown process, is analyzed by using phase-averaging, cross-correlation function and proper orthogonal decomposition. It is found that Reynolds shear stress is considerably increased in which the vortices roll up and then break down further downstream. In particular, rapid growth of vortices based on the “step mode” occurs at approximate half of the recirculation region, caused by in interaction between the shear layer and the recirculation region. Furthermore, the coherent structures, which are represented by a phase-correlated POD mode pair, are reconstructed in phases in order to show regular patterns of the subharmonic-perturbed coherent structures.

Extended Use of Coulomb’s Law in Relation to Established Laws within Electromagnetism

The competence of the basically electrostatic Coulomb's Law has historically been assumed to be restricted to pure electrostatics. As soon as electric charges were studied in motion, new sets of laws were introduced to explain the electromagnetic forces that are impelled by the motion. Among these new laws are Neumann's law of induction, Grassmann's force law, Lorentz' force law, and Ampere's force law. Furthermore, the difficulties in explaining the nature of light have given rise to the so-called wave-particle paradox. 1997 was the first year of the public circulation of research results that succeeded in showing that the basic force behind cases involving electricity or, more precisely, electromagnetism, can be derived from electrostatics. The aim of this article is to unify the results of existing theoretical research that discusses problems inherent within the prevailing standpoint on electromagnetism. In this paper, the conflict between the Lorentz Force Law and Ampere's Law is explored. Simultaneously, an alternative based strictly on electrostatics is closely examined. The very limited interest in this field of research, however, makes the amount of existing papers rather limited. The present study's new intervention is as follows: The so-called Ampe re forces between collinear currents, as in Ampere's bridge and in exploding wires, have been explained to be due to electrostatics, provided that the propagation delay dependant on the motion of charges is correctly taken into account. The Lorentz Force Law fails in this case. Additionally, electromagnetic induction can be explained by applying electrostatics, whereas the induction law fails. Light on the orbit electrons in the atoms involved in excitation and de-excitation of states can be explained using Coulomb's law (this has been widely disputed within science). The appearance of light at an atom hit by electromagnetic radiation can be shown to constitute a case of electromagnetic induction. The present study's conclusion is therefore that Coulomb's law is the only necessary force law within electromagnetism.

Plasma heating and acceleration in current sheets formed in discharges in argon

According to present notion, flares on the sun and other stars, substorms in magnetospheres of Earth and other planets, and disruptive instabilities in tokamak plasma are connected to development of current sheets in magnetized plasma. Therefore, current sheet dynamics and magnetic reconnection processes were studied actively during the last several decades. This paper presents the results of experimental studies of plasma heating and acceleration in current sheets formed in discharges in argon. The temperature and energy of directed motion of argon ions of different degrees of ionization were measured by spectroscopic methods. It was found that Ar II, Ar III and Ar IV ions are localized in different regions of the sheet. It was shown that Ampere forces applied to the sheet can accelerate the argon ions to observed energies.

Investigating influence of the magnetic arc blow in multi-break vacuum circuit breakers

This paper investigates the influence of the interactive magnetic field in multi-break vacuum circuit breakers (VCBs) on the arc plasma and the post-arc characteristics. The magnetic field of multi-break VCBs is asymmetric and off-center because of the interactive magnetic field, which is also called bias magnetic field (BMF). The BMF distribution of double-break VCBs is gained by electromagnetic analysis. The test circuit of the magnetic arc blow in multi-break VCBs is established by simplifying as the interaction between the vacuum arc and the BMF. The influence of the magnetic arc blow on the arc plasma is studied by the high-speed CMOS camera and the post-arc current measure. While the vacuum arc is in the direction of the Ampere force with the BMF at 200 mT, it is in the retrograde direction when the BMF is below 100 mT, which results in the post-arc charge obviously varying from 9 μC to 50 μC. The relationship between the BMF and the post arc charge is gained. The mechanism of the magnetic arc blow in multi-break VCBs is discussed. Therefore, this paper can provide the base of construct and configuration to avoid the influence of the magnetic arc blow.

General Classical Electrodynamics

Maxwell's Classical Electrodynamics (MCED) suffers several inconsistencies: (1) the Lorentz force law of MCED violates Newton's Third Law of Motion (N3LM) in case of stationary and divergent or convergent current distributions; (2) the general Jefimenko electric field solution of MCED shows two longitudinal far fields that are not waves; (3) the ratio of the electrodynamic energy-momentum of a charged sphere in uniform motion has an incorrect factor of . A consistent General Classical Electrodynamics (GCED) is presented that is based on Whittaker's reciprocal force law that satisfies N3LM. The Whittaker force is expressed as a scalar magnetic field force, added to the Lorentz force. GCED is consistent only if it is assumed that the electric potential velocity in vacuum, 'a', is much greater than 'c' (a ≫ c); GCED reduces to MCED, in case we assume a = c. Longitudinal electromagnetic waves and superluminal longitudinal electric potential waves are predicted. This theory has been verified by seemingly unrelated experiments, such as the detection of superluminal Coulomb fields and longitudinal Ampere forces, and has a wide range of electrical engineering applications.

Distributions of the ion temperature, ion pressure, and electron density over the current sheet surface

The distributions of the ion temperature, ion pressure, and electron density over the width (the major transverse dimension) of the current sheet have been studied for the first time. The current sheets were formed in discharges in argon and helium in 2D and 3D magnetic configurations. It is found that the temperature of argon ions in both 2D and 3D magnetic configurations is almost uniform over the sheet width and that argon ions are accelerated by the Ampere force. In contrast, the distributions of the electron density and the temperature of helium ions are found to be substantially nonuniform. As a result, in the 2D magnetic configuration, the ion pressure gradient across the sheet width makes a significant contribution (comparable with the Ampere force) to the acceleration of helium ions, whereas in the 3D magnetic configuration, the Ampere force is counterbalanced by the pressure gradient.

Experimental investigation and numerical simulation of triggered vacuum arc behavior under TMF/RMF-AMF contact

A series of triggering experiments was carried out to investigate the characteristics of vacuum arc controlled by TMF/RMF-AMF contacts. During all the experiments, the current ranged from 5–20 kA (rms) and both the arc appearance and behavior of cathode spots were captured by high-speed camera with corresponding arc current and arc voltage. A 3D steady magnetohydrodynamics (MHD) model was built to simulate and analyze the vacuum arc behavior under TMF/RMF-AMF contacts, and arc plasma parameters were calculated based on the above model. The experimental results showed that arc deflection was visible under both low and high current. Under high current, arc core formed, which meant the arc contracted significantly. In addition, the anode became much more active under high current. The behavior of the cathode spots showed that they split themselves into other new cathode spots. Under high current, the bulk of the spots rotated along a clockwise direction on a transverse magnetic field (TMF) plate, which caused much noise and oscillation in the arc voltage. The simulation results show that ions are likely to gather on the branches of the TMF plate on the anode plane, as a result of the effects between the electromagnetic force and pressure gradient of the arc plasma. The current contracts in the center of the TMF plate on the cathode which was due to the thin connecting rod there. The anode contraction of the current is caused by the Hall effect. Ions move along a clockwise direction on the TMF plate, which is driven by Ampere force. The current contraction resulted in significant melting in the center of the cathode surface while the other region suffered from uniform melting. The melting caused by the anode contraction is more significant than that of the cathode.

On the radial force balance in the quiet time magnetotail current sheet

AbstractUsing Time History of Events and Macroscale Interactions spacecraft observations of the quite magnetotail current sheet within the r∈[9,35]RE region (r is the radial distance from Earth and RE is Earth's radius), we investigate the thermal plasma pressure distribution along the magnetotail. Taking advantage of flapping motions of an ensemble of current sheets at various distances, we estimate the current density magnitude jy (in GSM coordinates). Comparing the tension force jyBz (Bz is the magnetic field component) with the radial gradient of the plasma pressure demonstrates that this gradient is only a small fraction, ∼10–15%, of the Ampere force exerted on the cross‐tail current, in the r > 15RE region. We also estimate the contribution of the electron temperature anisotropy to the pressure balance: in the r > 15RE region the corresponding force can balance only 10–15% of the observed tension force jyBz. Thus, we conclude that about 70% of the tension force is not balanced by the combination of isotropic radial pressure gradient or the electron anisotropy. We discuss mechanisms that could be responsible for balancing the magnetotail current sheet.

OES studies of plasmoids distribution during the coating deposition with the use of the Impulse Plasma Deposition method controlled by the gas injection

The article presents the results concerning the OES characterization of plasmoids generated by the Impulse Plasma Deposition method modified by the use of gas injection (Gas Controlled IPD). Both of the electrodes of the coaxial accelerator: the tube (cathode) and the rod (anode–the source of the vapors) are permanently connected with the capacitors charged to the high voltage of few kV value. During the coatings deposition both the electro-eroded vapors of the anode material (Ti) and the working gas (N2) form the plasmoids which are accelerated by the Ampere force in the coaxial accelerator and ejected to the vacuum chamber in the direction of non-heated substrates forming there the TiN coating. Periodic gas injections which make pressure fluctuations in the accelerator space in the range of critical values and cause the discharge to initiate or vanish accordingly with the chosen frequency. The promising practical effects of the use of gas injection for controlling the plasma processes during the coatings deposition by the GCIPD method was previously proved. On the basis of the present studies one can state that the GCIPD′ plasmoids containing multiple ions both of metallic as well as gas plasmoids constituents are more energetic as compared to the IPD case. Contrary to the IPD during the GCIPD the titanium fraction of the plasmoids structure overtakes the nitrogen one which seems to be important to the coating growth mechanism.

A non-invasive electric current sensor employing a modified shear-mode cymbal transducer

This paper presents a non-invasive sensor for electric current monitoring in electric power grid. The sensor consists of a modified shear-mode cymbal transducer and a Halbach array attached on the transducer. The Halbach array generates concentrated magnetic flux density on the side where the electric wire is placed and lowers the magnetic field on the other side. The wire experiences an enhanced Ampere force when energized, and the resulting reaction force of the Ampere force is further amplified by the cymbal transducer. The transducer works in shear mode and produces a voltage proportional to the applied electric current. At low frequencies, the sensor exhibits a flat voltage response. The non-resonant sensitivity of the sensor reaches ∼6.98mV/A over the frequency range of 10–80Hz with a separating distance of d=3.0mm. The average sensitivity is 6.97mV/A with high linearity at the power-frequency of 50Hz, and a small current step change of 0.05A can be clearly distinguished.

Threshold Magnetic Field Sensor Based on the Oscillator With a Magnetosensitive Piezoelectric Transducer in the Feedback

A threshold direct current magnetic field sensor with turn ON tunable level based on the oscillator containing a wideband amplifier, resistive voltage divider, as well as a resonance magnetosensitive transducer in the feedback loop has been described. The transducer is a bimorph plate of piezoelectric lead zirconate titanate with an electromagnetic coil wound on it. It uses a combination of the Ampere force, piezoelectric effect, and the acoustic resonance. The voltage transmission coefficient of the transducer depends on the dc magnetic field applied to the bimorph plate. Switching magnetic field of the oscillator can be tuned within the 5–600 Oe range by adjusting the parameters of the resistive voltage divider. The sensor is sensitive to the dc magnetic field direction.

Vacuum arc behavior and its voltage characteristics in drawing process controlled by composite magnetic fields along axial and transverse directions

In this research, drawing vacuum arc (VA) experiments were conducted using composite contacts under currents ranging from 5 kA to 20 kA root mean square (rms). The new type of contact comprised an axial magnetic field (AMF) configuration and a transverse magnetic field (TMF) configuration. The TMF plate was in the center, surrounded by the AMF plate. The contact generated both AMFs and TMFs simultaneously. VA appearances and arc voltages were recorded, and the VA was modeled as a conductor for electromagnetic force analysis in ANSYS software. The results showed that the coaxiality of operating mechanisms significantly influenced arc behavior just as the arc was ignited. When arc brightness did not increase after ignition, there was a voltage drop accompanied with diffusion of the VA. As to VA development, when an arc was ignited on an AMF plate, it spread on the plate and rotated. Over time the arc current increased, the constricting arc forms, and the arc column rotated on the TMF plate under the action of Ampere's force. With regard to the influence of a magnetic field on a VA at different stages, in the initial drawing arc stage the TMF was dominant, and the arc started to rotate under the action of Ampere's force. Afterwards, the AMF was dominant, with a steadily burning arc. As for contact melting, in the initial arcing period, a contracted short arc caused severe melting and erosion of the contact plate. When the ignition spot or root was close to the slot of plate, the electromagnetic force pushed the arc toward slot and contact edge, resulting in local erosion of the slot region.

Induction in the Dragged Dirac Sea of Particles-Antiparticles, Producing the Known E/M Waves, with Velocity C, with Respect to it

In this paper we specify the velocities involved in the Ampere absolute force, with absence of a single paradox, contrary to the multiple paradox theory of S. Relativity. The energy of a pair production of particles-antiparticles by a photon from the Dirac sea proves that this sea, which may be called an Eather, is comoving or dragged along with the motion of the Earth. Moreover, this Eather is always the basis with respect to which all the magnetic forces or better the Ampere forces, that all the correct magnetic forces originate from, should be defined with.

Focusing (Pinched) Flow of Pure Electrons, Evidence against Einstein’s Special Relativity

In this paper, in the following, we show that a flow (Filippova & Filippov, 2015) of pure electrons can never self-focus, according to Special Relativity. Thus, it is contrary to everyday experience because such beams do focus (P. T. Pappas, L. P. Pappas, & T. P. Pappas, 2014) in practice. Special Relativity is, thus, falsified. However, the Non-Realistic Absolute Cardinal Ampere Force is compatible with everyday experience. For example in the welding arc, we use at homes. The criterion is for which Theory; the Magnetic Attractive force overcomes the Coulomb Repulsive force of similar charges. This Magnetic force in S. Relativity never overcomes the Coulomb force. The Magnetic force is not a monopoly of Special Relativity. It is a force between moving charges, thus of Ampere force. Therefore, this force concerns the Ampere Electrodynamics (Maxwell, 1891), because, the Ampere force is exclusively a force between moving charges. Thus, in this paper, we compare the Coulomb repulsion of moving similar charges, with that of S. Relativity Lorentz force; and with that of Ampere. The results are for Special Relativity; the Lorentz forces never surpass the Coulomb forces. Though, the Ampere forces do surpass the Coulomb forces in many occasions, giving many examples, as they do happen in practice. Thus, S. Relativity is falsified. The Amper force and Ampere Electrodynamics has never been failed yet.

Gas rotation in discharges in a longitudinal magnetic field

This paper reviews theoretical and experimental work on gas rotation in discharges ignited in a longitudinal magnetic field. There is abundant evidence that such a field causes plasma-dust structures to rotate in the plane perpendicular to itself. This rotation cannot be explained solely by the dragging action of azimuthally moving ions. Drag is also exerted by the gas rotating under the moment produced by the Ampere force that arises in discharge regions with a nonuniform magnetic field near solenoid end faces and due to the narrowing of the discharge channel cross section. In a stratified discharge in a uniform magnetic field, an eddy electric current due to the noncollinearity of the plasma-density and temperature gradients brings the gas to rotation.

Gas rotation in discharge with moving strata in longitudinal magnetic field

The gas rotation in moving striations in a longitudinal magnetic field is examined. We study the case when the rotation is caused by the Ampere force affecting the eddy electric current which comes about because of a noncollinearity between gradients of the electron concentration and gradients of the temperature. Relations for the average velocity of gas rotation as a function of plasma parameters in the moving striations are obtained. Based on these relations, the estimations of average velocities are calculated for the typical experimental conditions.

A novel torsion testing technique for micro-scale specimens based on electromagnetism.

A novel torsion apparatus for micro-scale specimens is developed based on electromagnetism, in which a coil-magnet component is used for actuating and torque measuring. When the current gets through the coil, the torque, produced by Ampere force, can be easily measured by recording the current. A laser displacement sensor is applied to measure the rotation angle. The torque is calibrated using Sartorius BP211D balance. The calibration results demonstrate there is a perfect linear relationship between the torque and the current. The torque capacity is 4.0 × 10(-4) N m with noise-floor of less than 10(-8) N m. The rotation angle capacity is 60° with noise-floor of less than 0.02°. Two sets of copper wire specimens, with diameter of 100 μm and 140 μm, are tested using this apparatus. Experimental results, with good resolution and repeatability, successfully demonstrate the effectiveness of the torsion testing technique for micro-scale specimens.

The Claim that Neumann’s Induction Law Is Consistent with Ampère’s Law Rejected

There have been made several efforts to link Amperes law to different parts of electromagnetic field theory In this paper Neumann's effort to make his induction law to appear to be consistent with Ampere's law will be studied thoroughly., Since there exists a concept, named Ampere-Neumann electrodynamics, it has been regarded as necessary to analyze how Neumann derives the connection between induction and Ampere's force law. One conspicuous thing is that he by the electromotive force of the secondary loop is meaning a physical, mechanical force, contrary to what has usually has been understood as an induced voltage. This makes it possible for him to claim his ideas to be consistent with Ampere's law. On the contrary, recent papers have convincingly shown that the Continuity Equation of Electricity is able to explain, how a current is being induced in a secondary circuit, due to an alternate current in the primary circuit. Earlier discoveries that Coulomb's law is able to account for electromagnetic forces, without involving magnetic fields, provides the conceptual background, which makes the use of magnetic fields unnecessary also in connection with induction. Index Terms—Neumann's induction law, ampere's law, faraday's law of induction, grassmann's force law, coulomb's law.