scholarly journals Analytical-Numerical Approach to the Skin and Proximity Effect in Lines with Round Parallel Wires

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6716
Author(s):  
Paweł Jabłoński ◽  
Dariusz Kusiak ◽  
Tomasz Szczegielniak
Keyword(s):  
Current Density Distribution ◽  
Skin Depth ◽  
Proximity Effects ◽  
Wire Radius ◽  
True Solution ◽  
First Approximation ◽  
Depth Ratio ◽  
Spacing Ratio ◽  
The Wire ◽  
Communication Lines

Power and communication lines with round wires are often used in electrical engineering. The skin and proximity effects affect the current density distribution and increase resistances and energy losses. Many approaches were proposed to calculate the effects and related quantities. One of the simplest approximate closed solutions neglects the dimensions of neighboring wires. In this paper, a solution to this problem is proposed based on the method of successive reactions. In this context, the solution with substitutive filaments is considered as the first approximation of the true solution. Several typical arrangements of wires in single-phase communication lines or three-phase bus ducts are considered to detect the limits of applicability of the first approximation. The error of the first approximation grows with wire radius to skin depth ratio and wire radius to wire spacing ratio. When the wire radius to skin depth ratio is up to 1, and the gap between the wires is above the wire radius, the error is at a level of 1%. However, lowering the distance and/or skin depth leads to a much larger error in the first approximation.

scholarly journals Parallel Simulation of HGMS of Weakly Magnetic Nanoparticles in Irrotational Flow of Inviscid Fluid

2014 ◽  
Vol 2014 ◽  
pp. 1-12
Author(s):  
Kanok Hournkumnuard ◽  
Banpot Dolwithayakul ◽  
Chantana Chantrapornchai
Keyword(s):  
Magnetic Nanoparticles ◽  
Particle Transport ◽  
Parallel Simulation ◽  
Outer Radius ◽  
Inviscid Fluid ◽  
Wire Radius ◽  
Problem Size ◽  
Irrotational Flow ◽  
The Wire ◽  
Weakly Magnetic

The process of high gradient magnetic separation (HGMS) using a microferromagnetic wire for capturing weakly magnetic nanoparticles in the irrotational flow of inviscid fluid is simulated by using parallel algorithm developed based on openMP. The two-dimensional problem of particle transport under the influences of magnetic force and fluid flow is considered in an annular domain surrounding the wire with inner radius equal to that of the wire and outer radius equal to various multiples of wire radius. The differential equations governing particle transport are solved numerically as an initial and boundary values problem by using the finite-difference method. Concentration distribution of the particles around the wire is investigated and compared with some previously reported results and shows the good agreement between them. The results show the feasibility of accumulating weakly magnetic nanoparticles in specific regions on the wire surface which is useful for applications in biomedical and environmental works. The speedup of parallel simulation ranges from 1.8 to 21 depending on the number of threads and the domain problem size as well as the number of iterations. With the nature of computing in the application and current multicore technology, it is observed that 4–8 threads are sufficient to obtain the optimized speedup.

ATOMISTIC SIMULATION OF TORSIONAL VIBRATION AND PLASTIC DEFORMATION OF FIVE-FOLD TWINNED COPPER NANOWIRES

2014 ◽  
Vol 11 (supp01) ◽  
pp. 1344010 ◽  
Author(s):  
Y. G. ZHENG ◽  
Y. T. ZHAO ◽  
H. F. YE ◽  
H. W. ZHANG ◽  
Y. F. FU
Keyword(s):  
Plastic Deformation ◽  
Torsional Vibration ◽  
Partial Dislocation ◽  
Dislocation Nucleation ◽  
Activation Process ◽  
Torsional Angle ◽  
Wire Radius ◽  
Wire Length ◽  
Deformation Behaviors ◽  
The Wire

In this paper, atomistic simulations have been conducted to investigate the torsional mechanical behaviors of five-fold twinned nanowires (FTNs), including the torsional vibration properties, elasto-plastic deformation behaviors and activation process of the first partial dislocation nucleation. Simulation results show that the fundamental torsional vibration frequency is inversely proportional to the wire length and is independent of the wire radius. Provided that an effective shear modulus of FTNs is used, the classic elastic torsional theory may be applicable to nanoscale. Furthermore, it is found that the plastic deformation of FTNs is dominated by partial dislocation activities. The normalized critical torsional angle corresponding to the onset of plastic deformation increases with the decrease of the wire radius and temperature, while it is almost independent of the wire length and loading rate. In addition, the activation energy of the first partial dislocation nucleation is about several electric voltages and decreases with the increase of the wire radius and applied torsional load.

An adapted filament model for accurate modeling of printed coplanar lines with significant surface roughness and proximity effects

2010 ◽  
Vol 2 (3-4) ◽  
pp. 273-281 ◽  
Author(s):  
Brian Curran ◽  
Ivan Ndip ◽  
Christian Werner ◽  
Veronika Ruttkowski ◽  
Marcus Maiwald ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Transmission Line ◽  
Cross Sections ◽  
Skin Effect ◽  
New Technologies ◽  
Skin Depth ◽  
Proximity Effects ◽  
Roughness Effects ◽  
Average Deviation ◽  
The Impact

New technologies have resulted in transmission lines that deviate significantly from the intended rectangular cross sections. Trapezoidal cross sections and roughness that penetrate a significant depth into the surface in comparison to the skin-depth of the conductor can cause a very significant deviation in transmission line parameters from predicted values. Proximity effect further complicates the analysis by increasing losses and changing the impact of surface roughness by changing the current distribution. A skin-effect filament model that combines a traditional skin-effect filament modeling concept with traditional surface roughness modeling concepts is presented that accounts for surface roughness effects and non-ideal cross sections. The new technique models the transmission line non-idealities in a combined way with the current density in the signal and return current paths. This adapted filament model shows an average deviation of less than 2% above 1 GHz with one given transmission line measurement and does not have the computational challenges seen in a 3D full-wave solver.

Analysis of Wire Drawing and Extrusion Through Conical Dies of Small Cone Angle

1963 ◽  
Vol 85 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Betzalel Avitzur
Keyword(s):  
Cone Angle ◽  
Wire Drawing ◽  
Power Balance ◽  
Wire Radius ◽  
Process Variables ◽  
Power Losses ◽  
Uniaxial Load ◽  
The Wire ◽  
Analytical Expressions ◽  
Entrance Velocity

Analytical expressions are derived for the required front pull for wire drawing, as well as the back push for extrusion. The effect of each of the process variables on these forces is presented graphically. The process variables are: the cone’s semiangle (α) initial (Ri) and final (Rf) wire radius, material yield limit (σ0) at uniaxial load, back pull (σxb) and front pull (σxf), coefficient of friction (μ) or shear factor (m), die land (L), exit velocity (vf), and entrance velocity (vi). The power balance is set for these powers: (1) Internal power of deformation of the wire, (2) power involved with the back force on the wire, (3) power involved with the front force on the wire, (4) power losses due to friction between the wire and the die.

Melting of a Wire Anode Followed by Solidification: A Three-Phase Moving Interface Problem

2003 ◽  
Vol 125 (4) ◽  
pp. 661-668 ◽  
Author(s):  
S. S. Sripada ◽  
Ira M. Cohen ◽  
P. S. Ayyaswamy
Keyword(s):  
Ambient Medium ◽  
Boundary Surface ◽  
Interface Problem ◽  
Time Interval ◽  
Wire Radius ◽  
Ambient Conditions ◽  
Electrode Gap ◽  
Three Phase ◽  
The Wire ◽  
Solid Liquid

A fine metallic wire electrode is heated from below (by an electric discharge) causing melting and roll-up into a ball by surface tension. After the heating is terminated, a solidification front progresses through the melt until a solid ball is formed and cooled to ambient conditions. In this paper we numerically simulate the heating, melt motion and roll up and subsequent cooling and solidification. This is a three-phase problem (solid, liquid, and the ambient medium—plasma/gas) with two simultaneously moving phase interfaces, the outer one tracked by orthogonal grid generation conformal with the evolving boundary surface at each time interval. A novel observation in this study is that the wire end first drops until the melt radius equals the wire radius and then it begins to roll up into a ball consuming the wire. In other words, the inter-electrode gap first reduces and subsequently increases during an electronic flame off (EFO) discharge heating/phase-change process.

XV.—On the Thermo-Electric Properties of Charcoal and certain Alloys, with a Supplementary Thermo-Electric Diagram

1878 ◽  
Vol 28 (2) ◽  
pp. 321-343 ◽  
Author(s):  
C. G. Knott ◽  
J. G. MacGregor
Keyword(s):  
High Temperatures ◽  
Copper Wire ◽  
Electric Properties ◽  
Thin Wire ◽  
Thermo Electric ◽  
First Approximation ◽  
The Wire ◽  
Almost All

The determination by experiment of the thermo-electric relations of any one substance belonging to the electromotive series to all other such substances is sufficient to fix all mutual thermo-electric relations among these. The first endeavour of the experimenter is then to obtain as convenient a substance for this purpose as possible. In investigating charcoal and certain alloys, we have in almost all cases employed one or other of two alloys of platinum and iridium, which have been already used by Professor Tait for a like purpose. The wires we used were the same which he discusses in his “First Approximation to a Thermo-Electric Diagram,” under the names of M and N. Their complete freedom from oxidation, their elasticity, and the high temperatures of their fusing points, rendered them peculiarly suitable for thermo-electric investigations through long ranges of temperature.Generally both the M and N wires were firmly bound, each by its one extremity to the end or ends of the wire or wires respectively which were under investigation, in a multiple junction. This triple or, as it was in some cases, quadruple junction constituted the “hot junction.” The free extremities of the wires thus united were each bound to a moderately thin copper wire by very thin wire of the same metal, and the copper wires were led from these “cold junctions” to a commutator, which was in connection with a galvanometer. The commutator consisted of an arrangement of small mercury pools, into which the galvanometer and circuit wires, carefully amalgamated to ensure contact, dipped. All the junctions were formed in the manner indicated above, namely, by tightly binding the extremities of the wires together by thin copper wire.

scholarly journals Self inductance of a wire loop as a curve integral

2016 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
R. Dengler
Keyword(s):  
Cross Section ◽  
Mutual Inductance ◽  
Second Order ◽  
The Self ◽  
Wire Radius ◽  
Wire Length ◽  
Wire Loop ◽  
First Order ◽  
The Wire ◽  
Sharp Corners

It is shown that the self inductance of a wire loop can be written as a curve integral akin to the Neumann formula for the mutual inductance of two wire loops. The only difference is that contributions where the two integration variables get too close to each other must be excluded from the curve integral and evaluated in detail. The contributions of these excluded segments depend on the distribution of the current in the cross section of the wire. They add to a simple constant proportional to the wire length. The error of the new expression is of first order in the wire radius if there are sharp corners and of second order in the wire radius for smooth wire loops.

Influence of the Die Bearing Length on the Hydrogen Embrittlement of Cold Drawn Wires

2013 ◽  
Vol 577-578 ◽  
pp. 553-556 ◽  
Author(s):  
Jesús Toribio ◽  
Miguel Lorenzo ◽  
L. Aguado ◽  
Diego Vergara ◽  
Viktor Kharin
Keyword(s):  
Hydrogen Embrittlement ◽  
Hydrogen Diffusion ◽  
Cold Drawing ◽  
Wire Drawing ◽  
Wire Radius ◽  
Drawing Process ◽  
Strain Fields ◽  
Characteristic Value ◽  
The Wire ◽  
Definition Of

Prestressing steels, obtained by cold drawing, are highly susceptible to hydrogen embrittlement (HE) phenomena. Stress and strain fields produced by cold drawing play an essential role in this process since they affect hydrogen diffusion. Therefore, variations of such fields due to changes in drawing conditions could modify life in-service of these structural components. In this work the effect on HE of a parameter of the wire drawing process, thebearing length, is analyzed by means of diverse numerical simulations by the finite element method (FEM). The results of this work allow the definition of acharacteristic valueof the die bearing length equal to the wire radius, and demonstrate that the effects of stress-strain fields produced by wire drawing on HE are reduced when the bearing length exceeds such a characteristic value, so that the optimum cold drawing process is that with a bearing length higher than the wire radius.

Effect of Magnetic Field on the Momentum Relaxation Rate of Charge Carriers in a Size-Quantized Wire

2005 ◽  
Vol 277-279 ◽  
pp. 881-885
Author(s):  
Sh.G. Gasparyan
Keyword(s):  
Magnetic Field ◽  
Relaxation Rate ◽  
Surrounding Medium ◽  
Impurity Scattering ◽  
Dielectric Constants ◽  
Charge Carriers ◽  
Wire Radius ◽  
Inhomogeneity Parameter ◽  
Momentum Relaxation ◽  
The Wire

The effect of a longitudinal magnetic field and the dielectric constants mismatch of a size- quantized wire and surrounding medium on the impurity scattering of charge carriers is considered. The expressions for the momentum relaxation rate are carried out for scattering on charged Coulomb centers located on the wire axis. The dependences of the momentum relaxation rate on the magnetic field induction, dielectric inhomogeneity parameter, and also on the wire radius are obtained.

High-quality factor multipath differential fractal inductor for wireless applications

Circuit World ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sunil Kumar Tumma ◽  
Bheema Rao Nistala
Keyword(s):  
Integrated Circuits ◽  
Quality Factor ◽  
Skin Depth ◽  
Low Noise ◽  
Proximity Effects ◽  
High Quality Factor ◽  
Design System ◽  
High Quality ◽  
Content Type ◽  
Wireless Applications

Purpose The purpose of this study is to develop a high-quality factor fractal inductor for wireless applications such as satellite, WLAN, Bluetooth, microwave, radar and cellular phone. Design/methodology/approach The Hilbert fractal curve is used in the implementation of the proposed inductor. In the proposed inductor, the metal width has split into multiple paths based on the skin depth of the metal. The simulations of the proposed inductor are performed in 180 nm CMOS technology using the Advanced Design System EM simulator. Findings The multipath technique reduces the skin effects and proximity effects, which, in turn, decreases the series resistance of the inductor and attains high-quality factor over conventional fractal inductor for the equal on-chip area. Research limitations/implications The width of the path has chosen higher than the skin depth of the metal for a required operating frequency. Due to cost constraints, the manufacturing of the proposed fractal inductor is limited to a single layer. Practical implications The proposed inductor will be useful for the implementation of critical building blocks of radio frequency integrated circuits and monolithic microwave integrated circuits such as low-noise amplifiers, voltage-controlled oscillators, mixers, filters and power amplifiers. Originality/value This paper presents for the first time the use of a multipath technique for the fractal inductors to enhance the quality factor.

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