Journal of Electrostatics最新文献

{"title":"Cylindrical multipole expansion of electrostatic potential in form of triple sum of associated Legendre polynomials","authors":"Filip Vučić","doi":"10.1016/j.elstat.2024.103932","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103932","url":null,"abstract":"<div><p>We present multipole expansion of electrostatic potential in cylindrical coordinates which contains triple summation in terms of associated Legendre polynomials. Multipole moments of presented expansion depend only on charge distribution and can be easily calculated analytically for cylindrically symmetric and other charge distributions with simple representation in cylindrical coordinates. Presented multipole expansion is employed in order to calculate potential of uniformly charged solid cylinder. Correctness of derived multipole expansion is verified by comparing multipole expansion of potential produced by uniformly charged solid cylinder with known expression for potential on its axis.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103932"},"PeriodicalIF":1.8,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141068584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving lightning protection with corona minimising air terminals","authors":"F. D'Alessandro","doi":"10.1016/j.elstat.2024.103926","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103926","url":null,"abstract":"<div><p>A comprehensive approach to lightning protection is comprised of four key steps, namely protection against direct lightning strikes, dealing with surges and transients, dissipation of lightning currents via earthing and bonding, and protecting people. This paper deals with new research findings associated with direct-strike protection with lightning rods or “air terminals”, namely the effect of accumulated corona space charge around the tips of these components. There is now a great deal of consensus amongst lightning researchers and practitioners that space charge accumulation reduces the efficiency of an air terminal by inhibiting the initiation and development of an upward leader, a critical stage in the lightning attachment process. The paper describes measurements carried out in a high-voltage laboratory to quantify the amount of corona discharge that would be emitted under thunderstorm conditions from a variety of air terminals of different geometries. A unique, previously unreported aspect of these experiments was the corona testing of air terminals under dry and wet conditions. The results of these experiments showed that corona discharge (and hence space charge accumulation) from a standard Franklin rod is substantially higher than from the range of significantly blunter “corona minimising” air terminals that were tested. The previously reported polarity difference in corona characteristics was also observed, i.e., the magnitude of negative corona was larger than positive corona for the same ambient electric field. Differences in corona discharge were also observed under wet and dry conditions, where wet air terminals were found to produce modestly more corona. The paper then addresses the optimisation of air terminals, i.e., minimising corona discharge, for practical lightning protection applications, where the air terminal radius of curvature is tailored to its height and position of installation. Various researchers have made these calculations, the outcomes of which are summarised in this paper. In general, radii of curvature in the range 1–100 mm are required, depending on the installation height and location of the air terminal.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103926"},"PeriodicalIF":1.8,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141068583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The isoAdvector method for simulating deformation and breakup of multiple emulsion droplets responding to a DC electric field","authors":"Xin Huang ,&nbsp;Yijia Lu ,&nbsp;Yilong Li ,&nbsp;Xiaoming Luo ,&nbsp;Lin Teng ,&nbsp;Weidong Li ,&nbsp;Jiaqing Li ,&nbsp;Pengbo Yin","doi":"10.1016/j.elstat.2024.103933","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103933","url":null,"abstract":"<div><p>The droplet dynamic model under an electric field is established in this paper by coupling electric equations, multiphase flow equations, and isoAdvector interface capture method, accurately predicting the deformation and rupture characteristics of multiple emulsion droplets affected by an electric field. The evolutions of the flow field and electric field during the deformation and breakup processes of multiple emulsion droplets subjected to an electric field are elucidated and the effects of the electric capillary number <em>Ca</em> and the radius ratio <em>R</em>^∗ of the inner and outer droplets on the characteristics of droplet deformation and rupture are analyzed. The results show that in the silicone oil/water emulsion system, the inner droplet is difficult to induce charge since the electrostatic shielding effect of the outer droplet, and it has no impact on the equilibrium deformation of the outer droplet; whereas in the castor oil/silicone oil emulsion system, the charge is induced on the interfaces of both the internal and external droplets and the internal droplet has a remarkable impact on the equilibrium deformation of the external droplet. Furthermore, deformation-breakup phase diagrams of multiple emulsion droplets exposed to the electric field are obtained. As <em>R</em>^∗ increases, the <em>Ca</em>_c for droplet breakup decreases, indicating that the internal droplet intensifies the breakup of the external droplet. The results are significant for the promotion and application of electric field-driven droplet manipulation technology.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103933"},"PeriodicalIF":1.8,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140948736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the electromagnetic effects on the large floating roof oil tanks by nearby lightning strike based on TLM","authors":"Hamed Neyshabouri,&nbsp;Mohsen Niasati","doi":"10.1016/j.elstat.2024.103927","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103927","url":null,"abstract":"<div><p>Lightning fire is one of the biggest dangers for chemical and petrochemical storage tank farms, particularly in floating roof oil tanks (FROTs). To improve the lightning protection of FROTs, the process of floating roof tanks affected by lightning is analyzed. Lightning inductive effects can result in the undesired operation of the above-ground storage tank equipment and endanger exploitation safety. The time domain finite element analysis based on the transmission line model (TLM) method is regarded as a numerical technique to solve field problems by implementing circuit equivalents. This study aims to analyze lightning strike characteristics using the Heidler current function and simulate electromagnetic field strength (EMFS) distribution and surface current density (SCD). Calculation of minimum possible effective strike distance and shielding effectiveness (SE) is performed. Parametric modeling ensures accurate modeling of the roof's bypass conductor to the shell. By utilizing the Parameter Sweep technique, multiple simulations can be carried out with varying structure parameter values. This approach ensures optimal efficiency and accuracy in the results obtained.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103927"},"PeriodicalIF":1.8,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140650402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of the shape of Taylor cone in EHD printing based on backpropagation neural network and genetic algorithm","authors":"Yang Cheng ,&nbsp;Ran Huang ,&nbsp;Jianfeng Yu","doi":"10.1016/j.elstat.2024.103928","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103928","url":null,"abstract":"<div><p>Electrohydrodynamic (EHD) printing has been recognized as a promising additive manufacturing technology with superior pattern resolution and economic viability. The shape of Taylor cone is deemed a pivotal element for the amplification of deposition efficiency, and the maintenance of consistent operational steadiness in EHD printing. The correlations between diverse operating parameters and the shape of Taylor cone are presently not well investigated. In this paper, modeling of relationships between operating parameters and the shape of Taylor cone was conducted with a backpropagation neural network (BPNN) and a genetic algorithm optimized backpropagation (GA-BP) neural network. Taylor cone semi-vertical angle and the meniscus height were employed as two indexes to characterize the shape of Taylor cone. The prediction accuracies of BPNN model and GA-BP model were 92.79 % and 95.46 %, respectively. The GA-BP model demonstrated higher precision in forecasting the shape of Taylor cone. A predictive framework for the shape of Taylor cone was proposed, which provided a practical tool for process optimization in EHD printing.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103928"},"PeriodicalIF":1.8,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular dynamics promotes study of droplet electrocoalescence: A mini-review","authors":"Lingbo Huang ,&nbsp;Sai Huang ,&nbsp;Ling Chen ,&nbsp;Boping Ren ,&nbsp;Ping OuYang ,&nbsp;YuHan Li","doi":"10.1016/j.elstat.2024.103929","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103929","url":null,"abstract":"<div><p>Molecular dynamics simulations are used to study the mechanisms of droplet electrocoalescence and their importance in understanding the microscopic motion of matter and validating existing theories. This review summarizes recent advancements in the use of molecular dynamics simulations to study droplet electrocoalescence and its influencing factors. The limitations of current research and future directions for further development are discussed. The importance of studying the interactions between different components under the influence of electric fields is highlighted. Suggestions for future investigations are proposed based on the current research status.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103929"},"PeriodicalIF":1.8,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140553975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of size-resolved charge distributions for triboelectrically charged microparticles via electrical mobility analysis coupled to optical particle spectrometry","authors":"Rahaf A. Bahajry ,&nbsp;Sarah E. Ley ,&nbsp;José Morán ,&nbsp;Charles I. Skillman ,&nbsp;Kevin M. Romagnoli ,&nbsp;Christopher J. Hogan Jr.","doi":"10.1016/j.elstat.2024.103924","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103924","url":null,"abstract":"<div><p>In printing applications, microparticles are commonly triboelectrically charged with larger carrier particles. Here, we develop an impaction-differential mobility analyzer-optical particle spectrometer (DMA-OPS) system to examine the size-dependent charge distributions of toner particles in the 0.3 – 10 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> range resulting from triboelectric charging via acrylic-coated ferrite carrier. The toner-carrier blend is aerosolized, and toner particles are released from the carrier via inertial impaction of toner-carrier complexes. The toner particles are then classified by electrical mobility and their optical diameters are determined. We can produce toner particle size-dependent charge distributions, which can be converted to surface potentials, and charge-to-mass ratios.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103924"},"PeriodicalIF":1.8,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140550910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in electrostatic precipitation of particles from flue gases generated by domestic heating appliances. A brief outlook","authors":"Anatol Jaworek,&nbsp;Artur Marchewicz,&nbsp;Arkadiusz T. Sobczyk,&nbsp;Andrzej Krupa,&nbsp;Tadeusz Czech","doi":"10.1016/j.elstat.2024.103922","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103922","url":null,"abstract":"<div><p>Winter season is the time of increased emission of exhaust gases from household heating appliances containing particulate matter (PM) and other noxious contaminants. Many old buildings and single houses, particularly at rural and small town regions, still use stoves, fireplaces or ovens to flat heating. Besides qualified fuels like coal or biomass pellets, all kinds of wastes are also burned in many cases, producing not only mineral particles but also toxic volatile organic compounds or other carcinogenic species. To solve the problem of high level of emission of solid particles and organic-compound molecules different constructions of electrostatic precipitators, which can remove such particles, have been developed in last two decades, which were designed to operate downstream of small domestic boilers. Such electrostatic precipitator must comply with the ECODESIGN emission limits, which set the emission level at 20 mg/m³, for biomass. The mass collection efficiency should be higher than 95 % to obtain this emission level. This brief review presents different constructions of electrostatic precipitators designed to be used for the removal of fly ash particles from domestic heating appliances.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103922"},"PeriodicalIF":1.8,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140350496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of uniform charge assumption by investigating electrostatic charge distribution and potential during container filling: A numerical study","authors":"Manoochehr Fathollahi ,&nbsp;Sadreddin Mahmoodkalayeh","doi":"10.1016/j.elstat.2024.103925","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103925","url":null,"abstract":"<div><p>Using simulations, this study aims to investigate the actual charge distribution and resulting electrostatic potential during the filling process of a grounded metal barrel with low-conductivity diesel fuel. The flow rates used for loading were proposed based on the assumption of uniform charge distribution. Deviating from the uniform charge assumption, we observed local charge concentrations, including on the surface of the liquid. Despite the excessive surface charge, the maximum surface potential closely aligns with the prediction of the uniform charge assumption. This supports the practical viability of the proposed flow rates. Yet, considering a higher safety factor is advisable.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103925"},"PeriodicalIF":1.8,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140350497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oscillation suppression for pulsed arc electrohydraulic discharges based on plasma impedance model","authors":"Yingbo Yu,&nbsp;Zhongjian Kang","doi":"10.1016/j.elstat.2024.103923","DOIUrl":"https://doi.org/10.1016/j.elstat.2024.103923","url":null,"abstract":"<div><p>The circuit oscillation generated during the process of pulsed arc electrohydraulic discharge can prolong the discharge time and pose potential hazards to the withstand voltage of the discharge equipment. To enhance the anti-oscillation performance of the equipment, the structure of the gas spark switch was analyzed and an improved pulse power switch for suppressing circuit oscillation was designed. Firstly, a two-dimensional axisymmetric simulation model of the gas spark switch was established by COMSOL software, and a theoretical model to express the impedance of the plasma channel through the series combination of resistance and inductance was put forward. Then, the correctness of the theoretical model was proved by the nonlinear regression method considering the capacitance effect of plasma discharge, and the results show that the theoretical model almost coincides with the actual discharge waveform, with a fitting rate of 99.73%. Finally, a thyristor-based pulse power switch was designed, and an electrohydraulic discharge experiment was carried out. The experimental results show that the designed switch can reliably control the output of the high-voltage pulses even if the repetitive discharge frequency is higher than 60 Hz under 8.5 kV voltage. Furthermore, the circuit oscillation process was suppressed, and the oscillation time was reduced from 242μs to 39 μs, with a decrease of 83.88 %. This study has potential application value in underwater high-voltage discharge applications.</p></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"129 ","pages":"Article 103923"},"PeriodicalIF":1.8,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140343810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}