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Article
Publication date: 1 March 1991

S. ABDEL‐SATTAR

In this paper, the electrical parameters of the duct electrostatic precipitators with bundle wires, as discharge electrodes, are calculated and reported. Variation of…

Abstract

In this paper, the electrical parameters of the duct electrostatic precipitators with bundle wires, as discharge electrodes, are calculated and reported. Variation of mobility for both ions and particles in the space surrounding the energized subwires is taken into consideration. The method used is based on numerically solving the main set of equations, defining the ionized field surrounding the subwires of the bundle wire‐duct electrostatic precipitators (BWDEP) with the presence of dust particles. This method predicts the electrical performance in the BWDEP irrespective of the number of subwires per bundle. The corona onset voltage around the periphery of each subwire of the bundled discharge electrodes of the duct electrostatic precipitators is determined. It changes from point to point at the subwire surface. The effects of different numbers of subwires per bundled electrode, as well as the subwires arrangement, on the electrical performance of the BWDEP are also reported and discussed in this paper. The present findings are correlated to the physics of the electrical corona discharge.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 10 no. 3
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 January 1991

S. ABDEL‐SATTAR

In this paper a modified numerical method for calculating the precipitation efficiency of wire‐duct electrostatic precipitators is reported. Variation of mobility for both…

Abstract

In this paper a modified numerical method for calculating the precipitation efficiency of wire‐duct electrostatic precipitators is reported. Variation of mobility for both ions and particles in space surrounding the energized wires is taken into consideration. This method is based on solving numerically the main set of equations, defining the ionized field with presence of dust particles. The precipitation efficiency of the electrostatic precipitators is determined for the cement industry. The effect of different geometrical parameters on the precipitation efficiency is also reported. The precipitation efficiency of the wire‐duct electrostatic precipitator as influenced by both the applied voltage and the gas flow speed is discussed in this paper. The present findings are correlated to the physics of electrical corona discharge.

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COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 10 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 12 August 2019

Mozhde Heydarianasl

Electrostatic sensors are applied to measure velocity of solid particles in many industries because controlling the velocity particles improves product quality and process…

Abstract

Purpose

Electrostatic sensors are applied to measure velocity of solid particles in many industries because controlling the velocity particles improves product quality and process efficiency. The purpose of current paper is optimization of these sensors which is required to achieve maximum spatial sensitivity and minimum statistical error.

Design/methodology/approach

Different electrode of electrostatic sensors with different length, thickness and sensor separations were experimentally applied in laboratory. Then, correlation velocity, signal bandwidth and statistical error were calculated.

Findings

High sensor separation is a crucial factor because it would lead to increase signal similarity and decrease statistical error. This paper focuses on the effect of sensor separation on optimization of electrostatic sensors.

Originality/value

From observations, the optimal value for length, thickness and sensor separations was 0.6, 0.5 and 15 cm, respectively. Consequently, statistical error has improved by about 17 per cent. These results provided a significant basis of optimization of electrostatic sensors.

Details

Sensor Review, vol. 39 no. 5
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 16 November 2010

Francisc Bölöni, Abdelkader Benabou and Abdelmounaïm Tounzi

Electrostatic microelectromechanical systems are characterized by the pull‐in instability, associated to a pull‐in voltage. A good design requires an accurate model of…

Abstract

Purpose

Electrostatic microelectromechanical systems are characterized by the pull‐in instability, associated to a pull‐in voltage. A good design requires an accurate model of this pull‐in phenomenon. The purpose of this paper is to present two approaches to building finite element method (FEM) based models.

Design/methodology/approach

Closed form expressions for the computation of the pull‐in voltage, can provide fast results within reliable accuracy, except when treating cases of extreme fringing fields. FEM‐based models come handy when high accuracy is needed. In the first model presented in this paper, the FEM is used to solve the electrostatic problem, while the mechanical problem is solved using a simplified Euler‐Bernoulli beam equation. The second model is a pure FEM model coupling the electrostatic and mechanical problems iteratively through the electrical force. Results for both scalar and vector potential formulations for the FEM models are presented.

Findings

In this paper a comparative study of simple pull‐in structures is presented, between analytical and 3D FEM‐based models. A comparison with analytical models and experimental results is also realized.

Research limitations/implications

The coupling between the electrostatic and mechanical problem in the presented approaches, is iterative. Therefore, to improve the accuracy of the presented model, a strong coupling is needed.

Originality/value

In the presented FEM‐analytical model, the electrostatic problem is solved in both, scalar and vector electric potential formulations. This allows defining an upper and a lower limit for the electrostatic force and consequently for the pull‐in voltage.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 22 March 2013

Iliya Tizhe Thuku, Mohd Fua'ad Rahmat, Norhaliza Abdul Wahab, Teimour Tajdari and Abdulrahamam Amuda Yusuf

Circular pipelines are mostly used for pneumatic conveyance in industrial processes. For optimum and efficient production in industries that use a pipeline for conveyance…

Abstract

Purpose

Circular pipelines are mostly used for pneumatic conveyance in industrial processes. For optimum and efficient production in industries that use a pipeline for conveyance, tomographic image of the transport particles is paramount. Sensing mechanism plays a vital role in process tomography. The purpose of this paper is to present a two‐dimensional (2‐D) model for sensing the characteristics of electrostatic sensors for electrical charge tomography system. The proposed model uses the finite‐element method.

Design/methodology/approach

The domain is discretized into discrete shapes, called finite elements, by using a MATLAB. Each of these elements is taken as image pixels, on which the electric charges carried by conveyed particles are transformed into equations. The charges' interaction and the sensors installed around the circumference, at the sensing zone of the conveying pipeline are related by the proposed model equations. A matrix compression technique was also introduced to solve the problem of unevenly sensing characteristics of the sensors due to elements' number's concentration. The model equations were used to simulate the modeled electrostatic charge distribution carried by the particles moving in the pipeline.

Findings

The simulated results show that the proposed sensors are highly sensitive to electrostatic charge at any position in the sensing zone, thereby making it a good candidate for tomographic image reconstruction.

Originality/value

Tomographic imaging using finite element method is found to be more accurate and reliable compared to linear and filtered back projection method.

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Article
Publication date: 1 December 2004

R.V. Sabariego, J. Gyselinck, P. Dular, J. De Coster, F. Henrotte and K. Hameyer

This paper deals with the coupled mechanical‐electrostatic analysis of a shunt capacitive MEMS switch. The mechanical and electrostatic parts of the problem are modelled…

Abstract

This paper deals with the coupled mechanical‐electrostatic analysis of a shunt capacitive MEMS switch. The mechanical and electrostatic parts of the problem are modelled by the FE and BE methods, respectively. The fast multipole method is applied to reduce the storage requirements and the computational cost of the BE electrostatic model. An adaptive truncation expansion of the 3D Laplace Green function is employed. The strong interaction between the mechanical and electrostatic systems is considered iteratively.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 23 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 14 September 2010

Yu Okaue, Gaku Yoshikawa, Fumikazu Miyasaka and Katsuhiro Hirata

The purpose of this paper is to propose an analysis method of negative ion by electrostatic atomization. Because the electrostatic atomization includes large deformation…

Abstract

Purpose

The purpose of this paper is to propose an analysis method of negative ion by electrostatic atomization. Because the electrostatic atomization includes large deformation of a drop of water, it is difficult to analyze with conventional fluid analysis methods such as the finite differences method, the finite element method (FEM) and so on.

Design/methodology/approach

In this method, electrostatic field equation is coupled with Navier‐Stokes equation of a drop of water, employing the moving particle semi‐implicit method and FEM. The validity of the method is verified through the measurement.

Findings

It was found that the difference between calculated and measured results becomes large as the voltage increases.

Research limitations/implications

In order to improve the accuracy, it is necessary to improve the way to calculate surface tension and the analysis condition.

Originality/value

This paper confirms the usefulness of the numerical method to elucidate electrostatic atomization.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 8 January 2018

Mohamed Abd Alsamieh

The purpose of this is to study the mechanism of an oil film thickness formation in the nanoscale. A polar lubricant of propylene carbonate is used as the intervening…

Abstract

Purpose

The purpose of this is to study the mechanism of an oil film thickness formation in the nanoscale. A polar lubricant of propylene carbonate is used as the intervening liquid between contiguous bodies in concentrated contacts. A pressure caused by the hydrodynamic viscous action in addition to the double-layer electrostatic force, van der Waals inter-molecular forces and solvation pressure owing to inter-surface forces is considered when calculating the ultrathin lubricating films.

Design/methodology/approach

Using the Newton–Raphson iteration technique applied for the convergence of the hydrodynamic pressure, a numerical solution has been ascertained.

Findings

The results show that, at separations beyond about five molecular diameters of the intervening liquid, the formation of a lubricant film thickness is governed by the combined effects of viscous action and surface force of an attractive van der Waals force and a repulsive double-layer force. At smaller separations below five molecular diameters of the intervening liquid, the effect of the solvation force is dominant in determining the oil film thickness.

Originality/value

This paper fulfils an identified need to study the behavior of polar lubricants in concentrated contacts in ultrathin conjunctions. The effect of the hydrodynamic action, electrostatic force and surface action of van der Waals and solvation forces is considered when calculating the lubricant oil film thickness.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 November 2006

Alexander Bolonkin

To suggest a new revolutionary electrostatic linear engine.

Abstract

Purpose

To suggest a new revolutionary electrostatic linear engine.

Design/methodology/approach

Methods of the electrostatic physic are used for research.

Findings

Theory of this engine is developed and its possibilities researched.

Research limitations/implications

This engine gives a big thrust (up 4 × 105 N/m2), uses a high voltage electricity and light wires.

Practical implications

This engine can be used as a linear engine (accelerator), as a strong space launcher, as a high speed delivery system for space elevator, Earth‐Moon cable transport space, for an electrostatic levitation train, as a conventional high voltage rotating engine, as an electrostatic electric generator weapon (high speed gun), and so on. Theory of engine applications was developed and it shows powerful possibilities in space, transport and military industries. The projects are computed and show the good potential of the offered new concept.

Originality/value

Succeeds in proposing a new revolutionary electrostatic linear engine.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 6
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 December 1963

R.A. Coffee

Electrostatic projection methods are now well established as a primary means of corrosion protection and product finishing. Until about 18 months ago these methods were…

Abstract

Electrostatic projection methods are now well established as a primary means of corrosion protection and product finishing. Until about 18 months ago these methods were used almost exclusively for depositing paint surfaces, but they are now rapidly establishing themselves as techniques for plastics coating and vitreous enamelling. Compared with the conventional, compressed‐air‐spraying technique, the electrostatic method sometimes exhibits quite remarkable advantages, best known of which is the almost complete elimination of overspray. This arises from the ‘homing’ charge given to the atomised paint during the spraying operation.

Details

Anti-Corrosion Methods and Materials, vol. 10 no. 12
Type: Research Article
ISSN: 0003-5599

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