The Effect of Particle Concentration of Furnace Black on Field Intensity in the Air Gap of an Electric Precipitator

When high speed rail run at high altitudes, over-voltage occurred in the process of operating makes the air gap of cable connector breakdown. It is necessary to clear the electric field intensity distribution and its numerical size of cable connector to make an optimization in order to curb this phenomenon. For this reason, 1:1 finite element model is established by the use of ANSYS software, and the simulation results show that the maximum value of the electric field intensity of cable connector can reach 644.05 kV/m. The maximum electric field is reduced with adding an insulating jacket to the head of cable connector. When the thickness of the insulating jacket is respectively 3 mm, 5 mm, 7 mm, 10 mm, the maximum electric field intensity percentage decreased is 10.26%, 11.4%, 16.1%, and 16.7%. So the insulating jacket would be an effective measure to inhibiting the breakdown of the air gap at the cable connector.

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Alternating Current Discharge Characteristics and Simulation Analysis of Rod-Plane Short Air Gaps under Salt Fog Conditions

Energies ◽

10.3390/en11092251 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2251

Author(s):

Yunpeng Liu ◽

Shuo Jiang ◽

Zheng Zhong ◽

Jianghai Geng ◽

Fangcheng Lv

Keyword(s):

Electric Field ◽

Field Intensity ◽

Electric Field Intensity ◽

Alternating Current ◽

Discharge Voltage ◽

Air Gap ◽

Discharge Characteristics ◽

Air Gaps ◽

Ac Discharge ◽

Salt Fog

In this paper, smog meteorological conditions in the natural environment is simulated by the salt fog method. The study of the alternating current (AC) discharge characteristics of rod-plane short air gaps in salt fog environments has important guiding significance for how to strengthen the external insulation strength of ultra-high voltage (UHV) transmission lines and electrical equipment in smog environments. The rod-plane short air gap is selected as the model to simulate the extremely uneven electric field. The AC discharge test is carried out in the salt fog environment with different conductivity, and the finite element method (FEM) is used to simulate the distribution of electric field in air gap under salt fog environment conditions. The results show that under clean fog conditions the AC discharge voltage in the air gap increased by 15.1% to 35.5% compared to that under dry conditions. With the increased conductivity of salt fog, the AC discharge voltage in air gap decreased by 4.1% to 9.2% compared to that under clean fog conditions, and the reduction is within 10%. The distortion of the electric field and the adsorption of free electrons in the gap by droplets lead to the decrease of the electric field intensity in the air gap. With the increase of the conductivity, the electric field intensity in the air gap increases slightly. Meanwhile, the influence of salt fog and its conductivity on the AC discharge voltage of rod-plane short air gap is examined, becoming saturated with the increase of the gap distance and the conductivity of salt fog.

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The research of the electric field intensity change in the air gap of the compact electrostatic filter

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/450/7/072010 ◽

2018 ◽

Vol 450 ◽

pp. 072010

Author(s):

F R Ismagilov ◽

I Kh Khairullin ◽

M V Okhotnikov ◽

A A Nusenkis ◽

D V Maksudov

Keyword(s):

Electric Field ◽

Field Intensity ◽

Electric Field Intensity ◽

Air Gap ◽

Intensity Change ◽

Electrostatic Filter

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Study on the Attenuation Behavior of Acoustic Wave in ER Fluid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.605-607.960 ◽

2012 ◽

Vol 605-607 ◽

pp. 960-963

Author(s):

Nan Hui Yu ◽

Ji Jun Fan

Keyword(s):

Acoustic Wave ◽

Electric Field ◽

Field Intensity ◽

Particle Concentration ◽

Silicon Oil ◽

Er Fluid

The attenuation behavior of acoustic wave in ER fluid which was made by mixing starch in silicon oil was studied through experiments. The results demonstrate that the particle concentration of fluid and the intensity of extra electric field have certain influences on the attenuation behavior of acoustic wave passing through ER fluid. When othe conditions are fixed, the amplitude of acoustic wave passing through ER fluid increases along with the increasing of particle concentration or field intensity; meanwhile, the acoustic wave presents attenuation with the increasing of distance measured, and its trend slows down when the concentration or field intensity increases. The analysis indicates that the solidification effect of ER fluid caused by extra electric field may be the reason for these phenomena.

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Parameters of Nanosecond Overvoltage Discharge Plasma in a Narrow Air Gap between the Electrodes Containing Electrode Material Vapor

Ukrainian Journal of Physics ◽

10.15407/ujpe63.9.790 ◽

2018 ◽

Vol 63 (9) ◽

pp. 790

Author(s):

O. K. Shuaibov ◽

O. Y. Minya ◽

M. P. Chuchman ◽

A. O. Malinina ◽

O. M. Malinin ◽

...

Keyword(s):

Numerical Simulation ◽

Field Strength ◽

Electric Field ◽

Electric Field Strength ◽

Electrode Material ◽

Particle Concentration ◽

Discharge Plasma ◽

Simulation Method ◽

Air Gap ◽

Copper Vapor

Parameters of the nanosecond overvoltage discharge plasma in an air gap of (1÷5) × 10−3 m between the electrodes, which contains the vapor of an electrode material (Zn, Cu, Fe) injected into plasma due to the ectonic mechanism, have been studied. The dependences of those parameters on the ratio E/N between the electric field strength E and the particle concentration N in the discharge are calculated for the “air–copper vapor” system, by using the numerical simulation method.

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Attenuation Characteristics of Sound Wave in Silicon Dioxide ER Fluid

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.239-240.76 ◽

2012 ◽

Vol 239-240 ◽

pp. 76-79

Author(s):

Ji Jun Fan ◽

Nan Hui Yu

Keyword(s):

Silicon Dioxide ◽

Field Intensity ◽

Sound Wave ◽

Particle Concentration ◽

Propagation Distance ◽

Field Amplitude ◽

Sound Attenuation ◽

Electric Field Amplitude ◽

Er Fluid ◽

Attenuation Characteristics

The sound attenuation in ER fluid was experimentally studied. The results show that sound attenuation of ER fluid could be adjusted by the particle concentration of ER fluid and the intensity of electric field. Amplitude of sound wave in ER fluid increases with the increasing of particle concentration and field intensity; on the other hand, the attenuation of sound wave decreases with the increasing of propagation distance, as well as the particle concentration and field intensity. The experimental results indicate that the solidification effect of ER fluid is beneficial to the propagation of sound wave.

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A novel analytical calculation of magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-201505 ◽

2020 ◽

pp. 1-15

Author(s):

Jianqi Li ◽

Yu Zhou ◽

Jianying Li

Keyword(s):

Magnetic Field ◽

Conformal Mapping ◽

Permanent Magnet ◽

Flux Density ◽

Analytical Method ◽

Electromotive Force ◽

Analytical Calculation ◽

Air Gap ◽

Permanent Magnet Machines ◽

Peak Value

This paper presented a novel analytical method for calculating magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping. Firstly, flux density without slots and complex relative air-gap permeance of slotted air gap are derived from conformal transformation separately. Secondly, they are combined in order to obtain normalized flux density taking account into the slots effect. The finite element (FE) results confirmed the validity of the analytical method for predicting magnetic field and back electromotive force (BEMF) in the slotted air gap of spoke-type permanent-magnet machines. In comparison with FE result, the analytical solution yields higher peak value of cogging torque.

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Effects of contact gap on nondestructive evaluation using magnetic measurement for ferromagnetic steel

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209411 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 969-975

Author(s):

Hiroaki Kikuchi ◽

Yuki Sato

Keyword(s):

Magnetic Flux ◽

Nondestructive Evaluation ◽

Effective Permeability ◽

Magnetic Circuit ◽

Magnetic Measurement ◽

Air Gap ◽

Motive Force ◽

Hysteresis Curve ◽

Evaluation Technique ◽

Ferromagnetic Steel

We investigated effects of contact gap on magnetic nondestructive evaluation technique using a magnetic single-yoke probe. Firstly, we evaluated hysteresis curves and impedance related to permeability of the material measured by a single-yoke probe, when an air gap length between the probe and specimens changes. The hysteresis curve gradually inclines to the axis of the magneto-motive force and magneto-motive force at which the magnetic flux is 0 decreases with increasing the gap length. The effective permeability also decreases with increasing the gap thickness. The incremental of gap thickness increases the reluctance inside the magnetic circuit composed of the yoke, specimen and gap, which results in the reduction of flux applying to specimen.

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