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1 – 10 of over 2000
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 mobility for…

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

Article
Publication date: 14 June 2021

Jiachen Guo, Heng Jiang, Zhirong Zhong, Hongfu Zuo and Huan Zhang

Electrostatic monitoring technology is a useful tool for monitoring and detecting component faults and degradation, which is necessary for engine health management. This paper…

Abstract

Purpose

Electrostatic monitoring technology is a useful tool for monitoring and detecting component faults and degradation, which is necessary for engine health management. This paper aims to carry out online monitoring experiments of turbo-shaft engine to contribute to the practical application of electrostatic sensor in aero-engine.

Design/methodology/approach

Combined with the time and frequency domain methods of signal processing, the authors analyze the electrostatic signal from the short timescale and the long timescale.

Findings

The short timescale analysis verifies that electrostatic sensor is sensitive to the additional increased charged particles caused by abnormal conditions, which makes this technology to monitor typical failures in aero-engine gas path. The long scale analysis verifies the electrostatic sensor has the ability to monitor the degradation of the engine gas path performance, and water washing has a great impact on the electrostatic signal. The spectrum of the electrostatic signal contains not only the motion information of the charged particles but also the rotating speed information of the free turbine.

Practical implications

The findings in this article prove the effectiveness of electrostatic monitoring and contribute to the application of this technology to aero-engine.

Originality/value

The research in this paper would be the foundation to achieve the application of the technology in aero-engine.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 5
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 30 August 2022

Yan Zhang, Xianghu Ge, Xin Zhao, Xiaorui Yang, Shanghe Liu and Jingjing Xuan

The purpose of this paper is to research the induced flashover laws of different insulation materials under electrostatic electromagnetic pulse, and the induced flashover…

Abstract

Purpose

The purpose of this paper is to research the induced flashover laws of different insulation materials under electrostatic electromagnetic pulse, and the induced flashover characteristics of different electrode structures are further explored.

Design/methodology/approach

According to standard IEC 61000–4-2, an experimental system of electrostatic electromagnetic pulse flashover for insulation materials is established. The induction flashover laws of polytetrafluoroethylene, epoxy resin and polymethyl methacrylate surface-mounted finger electrodes under the different intensity of electrostatic electromagnetic pulse are researched. The influence of the finger electrode, needle–needle electrode and needle–plate electrode on insulation flashover was compared. Secondary electron emission avalanche (SEEA) and field superposition theory are used to analyze the experimental results of electrostatic electromagnetic pulse induced flashover.

Findings

The larger the dielectric strength of insulation materials, the more difficult flashover occurs on the surface. The field superposition enhances collision ionization between electrons and gas molecules, which leads to the insulation materials surface induced flashover easily by electrostatic electromagnetic pulse. The sharper the electrode shapes on the insulation materials surface, the stronger the electric field intensity at the cathode triple junction, more initial electrons are excited to form the discharge channel, which easily leads to flashover on the surface of the insulating material.

Originality/value

The proposed field superposition combined with the SEEA method provides a new study perspective and enables a more rational, comprehensive analysis of electrostatic electromagnetic pulse induced flashover of insulation materials. The work of this paper can provide a reference for the safety protection of spacecraft in orbit under a strong electromagnetic field environment, increase the service life of spacecraft and improve the reliability of spacecraft’s safe operation in orbit. It provides a basis for the selection of insulation materials for equipment under the different intensities of the external electromagnetic environment.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 March 2023

Zhirong Zhong, Heng Jiang, Jiachen Guo and Hongfu Zuo

The aero-engine array electrostatic monitoring technology (AEMT) can provide more and more accurate information about the direct product of the fault, and it is a novel condition…

Abstract

Purpose

The aero-engine array electrostatic monitoring technology (AEMT) can provide more and more accurate information about the direct product of the fault, and it is a novel condition monitoring technology that is expected to solve the problem of high false alarm rate of traditional electrostatic monitoring technology. However, aliasing of the array electrostatic signals often occurs, which will greatly affect the accuracy of the information identified by using the electrostatic sensor array. The purpose of this paper is to propose special solutions to the above problems.

Design/methodology/approach

In this paper, a method for de-aliasing of array electrostatic signals based on compressive sensing principle is proposed by taking advantage of the sparsity of the distribution of multiple pulse signals that originally constitute aliased signals in the time domain.

Findings

The proposed method is verified by finite element simulation experiments. The simulation experiments show that the proposed method can recover the original pulse signal with an accuracy of 96.0%; when the number of pulse signals does not exceed 5, the proposed method can recover the pulse peak with an average absolute error of less than 5.5%; and the recovered aliased signal time-domain waveform is very similar to the original aliased signal time-domain waveform, indicating that the proposed method is accurate.

Originality/value

The proposed method is one of the key technologies of AEMT.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

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 ions…

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.

Details

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

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

Keywords

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 this…

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

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.

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 by the FE…

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

Keywords

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 of a drop…

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

Keywords

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