Toni Viheriäkoski , Pasi Tamminen , Jeremy Smallwood , Paul Holdstock
{"title":"Investigating the human sensory threshold for electrostatic discharge using current waveform measurements","authors":"Toni Viheriäkoski , Pasi Tamminen , Jeremy Smallwood , Paul Holdstock","doi":"10.1016/j.elstat.2025.104192","DOIUrl":"10.1016/j.elstat.2025.104192","url":null,"abstract":"<div><div>Human perception thresholds are often used to highlight vulnerabilities of electrostatic discharge (ESD) sensitive devices. However, research on human sensory thresholds for ESD is limited, and voltage thresholds are frequently overstated within the electronics industry. Emerging evidence suggests that individuals may detect ESD at lower voltages than those cited in non-peer-reviewed sources. It is well established that standard test methods, do not accurately reflect real-world human metal discharge or human body discharge scenarios. Each discharge event can be considered unique. To address this issue, we recorded and analysed over 130 discharge current waveforms, measured with a 1 Ω current target, from eleven healthcare participants to better understand the characteristics of real human ESD events. It is assumed that the perception and sensing of ESD depend not only on source parameters such as voltage and capacitance but also on the characteristics of the resulting current waveform. To investigate this, each instance of ESD perception was linked to the corresponding current waveform. The statistical uncertainty of repeated ESD events was examined, and examples of variations in full discharge waveforms are presented. The test methodology is outlined in detail to support potential future research.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104192"},"PeriodicalIF":2.1,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265972","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}
M. Rahmani , N. Akhlaghipour , J. Taghinejad , A.R. Niknam
{"title":"Ion current density and sheath dynamics in low-pressure RF plasmas: A comparative study of particle-in-cell simulations and analytical calculations","authors":"M. Rahmani , N. Akhlaghipour , J. Taghinejad , A.R. Niknam","doi":"10.1016/j.elstat.2025.104194","DOIUrl":"10.1016/j.elstat.2025.104194","url":null,"abstract":"<div><div>The spatiotemporal evolution of plasma sheaths in low-pressure RF discharges is studied using particle-in-cell (PIC) simulations in conjunction with analytical calculations. The effects of RF voltage frequency, amplitude, and initial plasma density on sheath width, ion current density, and particle distributions are analyzed at multiple spatial locations over time. The results indicate that higher RF frequencies significantly enhance the ion current density due to increased space charge effects. Additionally, spatial mapping of peak ion current density demonstrates a strong dependence on RF voltage parameters. The temporal behavior of the ion current at both grounded and powered electrodes is characterized.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104194"},"PeriodicalIF":2.1,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265971","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}
Stefan H. Spitzer , Fabian Reitmeier , Enrico Danzi , Bretislav Janovsky , Michael Paul
{"title":"The Exploding Wire: A novel ignition source for the determination of safety characteristics of dusts and hybrid mixtures","authors":"Stefan H. Spitzer , Fabian Reitmeier , Enrico Danzi , Bretislav Janovsky , Michael Paul","doi":"10.1016/j.elstat.2025.104188","DOIUrl":"10.1016/j.elstat.2025.104188","url":null,"abstract":"<div><div>For the determination of safety characteristics of dusts there are mainly chemical igniters in use. Especially for the maximum explosion pressure and the maximum rate of pressure rise there is no standard with another ignition source. The chemical igniters have the disadvantage of being very hard to obtain in most countries and they are even illegal in some. This leads to the fact, that those countries are not able to investigate the safety characteristics or only with a high effort by sending dust samples to facilities outside the country. This article presents a novel ignition source and describes how to build it. It is also the first step to place this ignition source into the dust standards in the future.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104188"},"PeriodicalIF":2.1,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265969","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":"High-voltage electrostatic slides: Are they still relevant for teaching in the era of numerical simulations?","authors":"Pedro Llovera-Segovia , Josep Simón-Castel , Vicente Fuster-Roig , Alfredo Quijano-López","doi":"10.1016/j.elstat.2025.104179","DOIUrl":"10.1016/j.elstat.2025.104179","url":null,"abstract":"<div><div>The teaching of electrostatics has been a cornerstone of physics and engineering education for centuries. Its focus has evolved significantly, transitioning from a 19th-century practical approach represented by Ganot's textbooks to a predominantly theoretical treatment in the 20th century, often presented as an introductory course to more complex electromagnetic problems. By the time the industrial applications of electrostatics, became prominent in the mid-20th century (particularly in plastics manufacturing), practical electrostatics had largely disappeared from student textbooks. However, during the first half of the 20th century, specialized companies began to develop science education tools for schools and universities which included electrostatics demonstrations. In Spain, ENOSA became a remarkable example, producing a wide range of educational materials for teaching science. Among their contributions were materials designed to demonstrate electrostatic principles. Notably, this company developed slides for visualizing electrostatic fields using specific electrode arrangements, an overhead projector, and a Van de Graaff generator. These slides contained cells filled with insulating oil and magnetic insulating particles, which visually aligned and moved when exposed to high-voltage potentials applied to the electrodes. This work outlines a brief history of these electrostatic demonstration slides and provides a detailed description of how they were designed to be used, based on ENOSA's reference materials and practical experience. Furthermore, it compares the educational value of these physical demonstrations with modern simulation techniques, such as finite element software. The pedagogical question of this study is whether these electrostatic slides remain relevant in contemporary electrostatics courses. Are these physical demonstration tools worth the effort and risks associated with their setup, or have finite element simulations in the classroom rendered them obsolete? From the students' perspective, what are the educational benefits of these traditional tools compared to modern software-based approaches?</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104179"},"PeriodicalIF":2.1,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265970","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}
Marcela Efmertová, Jan Mikeš, Ivan Soukup, Ondřej Hanuš
{"title":"Rotating elements in early lightning protection: Bridging Diviš’s 18th century innovation with contemporary wind turbine physics","authors":"Marcela Efmertová, Jan Mikeš, Ivan Soukup, Ondřej Hanuš","doi":"10.1016/j.elstat.2025.104187","DOIUrl":"10.1016/j.elstat.2025.104187","url":null,"abstract":"<div><div>This study investigates the relationship between Václav Prokop Diviš’s 1754 lightning rod design and contemporary research on lightning interactions with wind turbines. Through comparative analysis of historical sources and modern experimental findings, we explore how Diviš’s incorporation of rotating elements and multiple discharge points shows interesting parallels with physical phenomena observed in modern wind turbine research. While Diviš’s complete system failed due to implementation limitations, certain individual design elements show correspondence with effects documented in contemporary studies: rotation-enhanced electrical activity and multi-point discharge characteristics. This historical-modern connection illustrates how empirical experimentation can explore concepts that later scientific research examines with modern methodology. The study contributes to understanding the evolution of atmospheric electricity knowledge and the persistence of certain experimental approaches across centuries.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104187"},"PeriodicalIF":2.1,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265968","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}
Norman Sepsik , Zoltán Ádám Tamus , István Kiss , Ferenc Ender
{"title":"A measurement method for testing textile materials charging for self-charging electrostatic face masks application","authors":"Norman Sepsik , Zoltán Ádám Tamus , István Kiss , Ferenc Ender","doi":"10.1016/j.elstat.2025.104190","DOIUrl":"10.1016/j.elstat.2025.104190","url":null,"abstract":"<div><div>Electrostatic masks are significantly more effective than conventional mechanical masks due to their enhanced filtration efficiency. The charge of filtering textiles is generated by friction between two layers due to the spontaneous movement of the mask under wearing. However, the filtrating efficiency is diminished over time as the electrostatic charge decays, especially in humid environments. An essential requirement would be to compare the filling properties of various textiles used for masks by reliable measurement to produce more effective masks. However, no standardized procedure exists for measuring the charge of textiles. In this paper, a new test arrangement and protocol were developed to measure textiles’ charging due to friction accurately is presented. The new test system is built up from a stationary sample holder and a movable element holding another sample to simulate friction between the layers and ensure the measurement repeatability. The surface charge of tested textiles was measured using a parallel plane electrode system positioned 0.5 cm above the textile, connected to a high-impedance voltmeter. The tested textiles’ initial charging can be determined by measuring the voltage of plane electrode. The results demonstrate that the newly developed test setup enables testing the charging capabilities of various mask filters and ensuring the comparability of various textile materials.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104190"},"PeriodicalIF":2.1,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226896","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}
Luhan Zu , Stéphane Holé , Nicolas Lallouet , Christian-Éric Bruzek
{"title":"Influence of polypropylene content in PPLP for high voltage insulation at cryogenic temperature","authors":"Luhan Zu , Stéphane Holé , Nicolas Lallouet , Christian-Éric Bruzek","doi":"10.1016/j.elstat.2025.104164","DOIUrl":"10.1016/j.elstat.2025.104164","url":null,"abstract":"<div><div>This study compares the dielectric performance of polypropylene-laminated paper (PPLP) insulation impregnated with liquid nitrogen in the context of high-power superconducting cables within the SCARLET European project. Samples with polypropylene (PP) contents of 43 % and 55 % are tested in a representative cable geometry including almost 20 % gap density in the insulation. Breakdown voltage is found to increase with hydrostatic pressure. Weibull analysis predicts similar breakdown field strength at 63 % probability for both kinds of samples (about 89 kV/mm) but a larger scale parameter for 55 %-PP-content sample (about 10 versus 7). This better performance for 55 % PP content is mitigated by a larger brittleness upon breakdown.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104164"},"PeriodicalIF":2.1,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226882","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":"PWP measurement of charge distribution in dielectric and conductive liquids under DC electric field","authors":"V. Berry , P. Leblanc , S. Hole , T. Paillat","doi":"10.1016/j.elstat.2025.104182","DOIUrl":"10.1016/j.elstat.2025.104182","url":null,"abstract":"<div><div>All liquids exhibit non-zero electrical conductivity, revealing the presence of electric charges. Though often considered uniformly distributed, these charges are influenced by interfaces (electrical double layer) or external electric fields. Their local accumulation can affect the performance of power equipment. Few precise methods exist to measure charge distribution in liquids. The PPRIME Institute has been adapting solid-state techniques, such as the Pressure Wave Propagation (PWP) method, for use in liquids. These have enabled the observation of how charges spatially and temporally reorganize under a DC electric field in dielectric and conductive liquids.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104182"},"PeriodicalIF":2.1,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226883","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":"Optimizing electric field uniformity of a segmented-electrode free-fall separator using RSM-FEM coupling","authors":"Abdelkader Nadjem , Karim Rouagdia","doi":"10.1016/j.elstat.2025.104191","DOIUrl":"10.1016/j.elstat.2025.104191","url":null,"abstract":"<div><div>Electrostatic separation enables the efficient sorting of mixed granular insulating materials by applying controlled electrical and mechanical forces. Although particle separation requires a strong electric field (E-field), a uniform field distribution is critical to achieving consistent particle deflection and high separation efficiency. This study aimed to analyze the E-field non-uniformity (NUF) in free-fall electrostatic separator design incorporating segmented electrodes and inter-electrode side openings to mitigate particle rebound. Numerical simulations were conducted to optimize critical parameters—number of electrode pairs, inclination angle, and segmented length ratio—using a coupled computational approach: finite element analysis (FEM) in COMSOL Multiphysics for field modeling, integrated with response surface methodology (RSM) <em>via</em> central composite design (CCD) in JMP statistical software for parametric optimization. Key performance metrics included E-field NUF and the total distance between same-polarity electrodes. Quadratic regression modeling identified the optimal configuration to be eight electrode pairs with a segment length of 4.16 cm and an inclination angle of 16.88°, achieving 86 % desirability. Simulation results showed a strong correlation with model predictions (R<sup>2</sup> > 0.99). Statistical analysis revealed that the number of electrode pairs was the most influential factor affecting E-field NUF, contributing to 49.75 % of the observed variance. Similarly, the segmented electrode length ratio had the strongest impact on inter-electrode distance, accounting for 65.91 % of the response variation. Compared to conventional configurations, the proposed design reduces E-field NUF by 44 %, demonstrating its potential for enhanced electrostatic separation performance.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104191"},"PeriodicalIF":2.1,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145226891","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}
Donghyeon Kim, Jiwon Jeong, Jiyoung Ko, Jongjin Lee
{"title":"Power characteristics of a classical Wimshurst machine","authors":"Donghyeon Kim, Jiwon Jeong, Jiyoung Ko, Jongjin Lee","doi":"10.1016/j.elstat.2025.104189","DOIUrl":"10.1016/j.elstat.2025.104189","url":null,"abstract":"<div><div>This study examines the discharge characteristics and power response of a Wimshurst machine. Two discharge regimes exist: a linear region with increasing voltage and period, and a saturation region with delayed discharges and voltage limits. The transition stems from changes in electric field distribution of the spherical air-spark gap. The peak discharge power shifted with the needle-to-plate gap, highlighting the balance between charge collection and dissipation. These results provide a quantitative basis for understanding electrostatic discharge and optimizing air gap conditions in electrostatic energy harvesting systems.</div></div>","PeriodicalId":54842,"journal":{"name":"Journal of Electrostatics","volume":"138 ","pages":"Article 104189"},"PeriodicalIF":2.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227030","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}