Electrostatic Discharge Research Articles

Origin of the recirculation flow pattern induced by nanosecond discharges and criterion for its development

Abstract Nonequilibrium plasmas generated by spark discharges induce chemical, thermal, and flow dynamic effects that are beneficial in many applications such as plasmalysis, plasma-assisted combustion, and plasma flow control. Among the flow dynamic effects generated by these discharges, vorticity is of particular interest because it enhances the mixing of the discharge products with the surrounding environment and accelerates the cooling of the kernel. This article provides a comprehensive examination of the vorticity produced by nanosecond discharges in air. Using computational fluid dynamic simulations of the blast wave resulting from energy deposition in the interelectrode volume during the nanosecond pulse, we analyze the various sources of vorticity during the post-discharge period. The non-uniform strength of the leading shock of the blast wave is found to be the primary promoter of vorticity. Other sources, such as the barocline torque, play a secondary role in explaining the overall recirculation pattern. In addition, the discharge cooling mechanisms are also investigated. The cooling regimes and their efficiencies are classified according to the discharge parameters, such as the inter-electrode gap, the initial kernel temperature, or the frequency of repetitive pulses. Finally, a physics-based, non-dimensional number π*, equal to the ratio of the initial kernel temperature to the ambient temperature, is introduced. A numerical analysis shows that the transition between the recirculating and non-recirculating flow regimes occurs for π* on the order of 10. This criterion is validated against experimental and numerical results from the literature.

Reaching New Efficiency Milestones in Low‐Speed Wind Energy Harvesting via Noncontact Stackable Ion‐Gate‐Based Static Discharge Generator

AbstractWind energy harvesting is attracting increasing interest owing to the growing global electric energy production. However, energy generation using existing wind turbines is deficient compared to the potential of wind energy owing to less‐efficient wind turbines operating at low wind speeds. Therefore, an ion‐gate‐based static discharge generator (ISDG) with a charge suppliance turbine (CST) for efficient low‐speed wind energy harvesting is introduced. CST comprises a charge suppliance rotator (CSR) and Savonius wind blades, where the CSR generates electrical charges for inducing Townsend discharge at the ion gate; thus, the current output gets enhanced owing to an avalanche effect. Additionally, the CSR in the CST can be operated with a stacked structure and noncontact movement, allowing the device to generate high power with a low input. Thus, an ISDG comprising CST can generate electricity with wind blowing at 3 and 4 m s−1 at high efficiencies of 21.9% and 32.8%, respectively.

Investigation on the electrostatic characteristics and discharge dynamics of non-uniformly charged powder in silos

Investigation on the electrostatic characteristics and discharge dynamics of non-uniformly charged powder in silos

A study on the preparation, antimicrobial property and durability of Ag-based coating deposited by electric spark discharge with silver nitrate solution

A study on the preparation, antimicrobial property and durability of Ag-based coating deposited by electric spark discharge with silver nitrate solution

A Review on Thermal and Electrical Hazards in the Pharmaceutical Industry

Thermal and electrical hazards in the pharmaceutical industry pose a significant risk to operational safety, product integrity, and regulatory compliance. These risks arise from the high-temperature processes of exothermic reactions, electrostatic discharge, and electrical system malfunctions. As advanced technologies in continuous manufacturing and high-speed automation are increasingly integrated, the complexity and magnitude of these hazards are accelerating. According to research findings, thermal and electrical breakdowns represent over 60% of accidents in this sector, an aspect that emphasizes the greater need for advanced safety techniques. This paper compiles all current information that would define the causes and implications of hazards in this review. This focuses on many often neglected critical factors, including high energy content in processes, the volatile nature of solvents, and inadequately developed safety systems. The latest innovations in hazard mitigation, such as predictive maintenance using IoT-enabled sensors, dynamic thermal management systems, and AI-based fault detection algorithms, have demonstrated good potential for reducing incident rates. Additionally, adherence to evolving standards like ISO 45001 and advanced Occupational Safety and Health Administration (OSHA). compliance frameworks is essential for addressing these risks effectively. This review underscores the need to integrate advanced safety technologies and robust risk management frameworks by identifying gaps in current safety practices and proposing evidence-based strategies for ensuring sustainable and compliant pharmaceutical operations. Keywords: Thermal Hazards, Electrical Hazards, Pharmaceutical Industry Safety, Workplace Hazards in Pharma, Occupational Safety in Pharmaceuticals, Industrial Electrical Safety

Synthesis and Characteristics of 1,2,4,5-Tetrazines for Using as High Energy Density Materials (HEDMs)

Nitrogen-rich heterocycles constitute a family of high energy density materials (HEDMs) that have been developing intensively in recent years. A representative of this class is 1,2,4,5-tetrazine, a six-membered aromatic compound containing four nitrogen atoms in the ring. Many energetic compounds with this scaffold exhibit thermal stability, high density, and insensitivity to various stimuli, including friction, impact, and electrostatic discharge. This review presents methods for constructing 1,2,4,5-tetrazine precursors from acyclic reagents and describes their chemical modifications, leading to new energetic compounds with potential applications in the industry as explosives, propellants, or pyrotechnics. Synthetic procedures and reaction conditions are discussed, along with the detonation parameters of new nitrogen-rich tetrazine-based products, which allow estimation of their application potential.

Electrostatic discharge failure and protection of single-walled carbon nanotube field-effect transistors

Abstract Carbon nanotube based field effect transistors (CNT-FETs) have been considered as a preferred alternative to the traditional Si-based MOSFETs. Here we investigated the electrostatic discharge (ESD) failure characteristics of single-walled CNT (SWCNT) FET. In ESD event, the instantaneous high current will generate an amount of heat in the CNT-FET channel resulting in its thermal failure owing to its randomly aligned SWCNT networks. The CNT-FET failure mechanism and its ESD characteristics with various key parameters are studied in detail. These insights provide new ideas and a guidance for the research and application of CNT-FETs. In order to achieve a full chip ESD protection network for CNT chips, we referred to commonly used ESD devices in silicon-based processes and designed CNT based ESD devices, including GD-CNT-FET (Gated-VDD CNT-FET) and RC-CNT-FET (RC trigger CNT-FET). CNT-FET with randomly aligned SWCNT networks, whose failure current level is only about 50µA/µm, needs larger areas to achieve effective ESD protection.

Characterization of a simple gas expansion ion source for intense pulses of subthermal molecular ions.

We describe a simple gas expansion ion source based on static discharge voltages and a commercially available pulsed valve. The discharge is initiated by the gas pulse itself between two high voltage electrodes, without the need for fast voltage switches or complex timing schemes. The ion source very reliably produces intense bursts of molecular ions (with currents exceeding 100 μA during the pulse-on phase) with only minor pulse-to-pulse variations in intensity and pulse shape. We have characterized the internal energy of H3+ and N2O+ ions produced by the ion source, using dissociative charge exchange and laser photodissociation, respectively. We find that collisions in the expanding gas reduce the internal energy of the molecular ions to well below room temperature.

Electromagnetic radiation attenuation materials

The shielding electromagnetic (EM) waves is a very important field of the electronics, telecommunications and IT industries. The phenomenon of electromagnetic interference (EMI) can be a source of interference in electronic systems, which can both disrupt the operation of systems and provide a breach to intercept the flow of classified information. Hence, it is necessary to shield electronic and IT systems to prevent the coupling of circuits and prevent the monitoring of data emitted in the form of electromagnetic waves. An additional threat resulting from the EMI phenomenon is the possibility of inducing high voltages and currents in circuits that may temporarily or permanently damage electronic systems as a result of high-power electromagnetic pulses. Examples of sources of high-power impulses can be, for example, atmospheric discharges, gasoline engine ignition systems, electrostatic discharges, solar discharges, cosmic rays and military hardware, such as electromagnetic directed energy weapons. The paper will present the results of research carried out as part of interdisciplinary projects related to security threats to ICT systems in the area of critical infrastructure.

Atomization Performance of Spray Nozzles and Their Influence on Fine Particle Collection in the Wet Electrostatic Precipitator

The wet electrostatic precipitator (WESP) is crucial for the ultra-purification of blast furnace gas in gas-fired generator units. To address issues like high water consumption, poor atomization leading to spark discharge, and uneven water mist distribution, a water mist testing system using a laser particle-size analyzer was established. Eight spray nozzles were tested to identify the optimal atomization performance and operating parameters. The effect of chemical agglomeration agents on nozzle atomization and particle capture efficiency was also examined. The results show that the atomization effect was the best when the operating water pressure was 0.5 MPa. The D50 of the blast furnace dust increased from 8.529 μm to 20.30 μm after electrostatic precipitation when the 1/8 rotating core nozzles were installed in the WESP, and the proportion of dust particles whose diameter is ≤5 μm decreased by 20.09% compared with the dust emitted from the inlet. The total dust removal efficiency reached 83.41%. With chemical agglomeration, the D50 reached 24.88 μm, and removal efficiency rose to 96.98%. Among the tested nozzles, the 1/8 rotating core nozzle was the most effective, combining superior atomization, maximum dust removal efficiency, and minimal water consumption, making it ideal for blast furnace gas purification.

Performance Evaluation of Microtik Routers According to Electromagnetic Compatibility Testing Standards

This study presents a detailed analysis of the performance of the MikroTik router, model RB912UAG-2HPnD, according to European and international electromagnetic compatibility test standards. Tests included measurements of conducted and radiated emissions, harmonic current emissions, flicker and voltage fluctuations, as well as evaluation of equipment immunity to radiated electromagnetic fields, conductive induced radio disturbances, electrostatic discharges and rapid voltage pulse trains in accordance with the product standard SM EN 301 489-1, the emission requirements standard SM EN 55032, and the standard series for immunity tests SM EN IEC 61000. The test results showed that the router complies with all necessary requirements, with significant passing margins above the established limits. For example, the conducted emissions from the power and network ports had minimum pass margins of -14.33 dB to 23.128 MHz and -9.29 dB to 23.128 MHz, respectively. Radiated emissions below 1 GHz and above 1 GHz demonstrated compliance without exceeding the established pass margins. Electrostatic discharge tests and exposure to radio frequency electromagnetic fields confirmed that the router meets the specified performance criteria, ensuring proper operation under electromagnetic interference conditions. Measurements of harmonic current and voltage and flicker fluctuations indicated the router's compliance with applicable standards, demonstrating a power consumption below 75 W and a level of voltage fluctuations that does not affect equipment performance. During and after the immunity tests, the router performed as intended with no loss of functionality or critical stored data. These results emphasize the reliability and stability of the MikroTik router, highlighting the importance of compliance with strict electromagnetic compatibility standards for use in critical environments. The evaluation provides a solid basis for adapting the router to applications that require strict electromagnetic standards, ensuring robust and reliable performance.

Engineering Triboelectric Paper for Energy Harvesting and Smart Sensing.

Triboelectric nanogenerators (TENGs) represent a promising technology for energy harvesting and self-powered sensing with a wide range of applications. Despite their potential, challenges such as the need for cost-effective, large-area electrodes and engineering sustainable triboelectric materials remain, especially given the impending restrictions on single-use engineering plastics in Europe. To address these challenges, engineering nano-graphite-coated paper is presented as a sustainable and high-performance alternative for triboelectric layers. Moreover, this material, which can be produced on an industrial scale, offers a viable replacement for metal electrodes. The combination of nano-graphite and paper, with its large contact area and inherent surface roughness, enables ultra-high power densities exceeding 14 kWm-2, driven by electrostatic discharge at the surface. Beyond energy harvesting, smart sensors are developed for floors and walls that detect movements for security purposes and smart sheets that monitor body movements and physiological activities during sleep. The findings highlight the potential of this engineering paper to serve as an eco-friendly alternative to engineering plastics in TENGs and electrodes, opening new avenues for future applications.

Calculated determination of spark discharge parameters in capacitive ignition systems of gas turbine engines based on diagnosing voltages on storage capacitors

The calculation results of the spark discharges probabilistic parameters in semiconductor spark plugs of capacitive ignition systems are presented: the energy and duration of discharges, discharge current and the criterion for the ignition ability of ignition systems based on measurements of two diagnostic quantities when it is impossible to directly measure these parameters under the conditions of gas turbine engines and full-scale test benches. Two voltages on the storage capacitor of ignition systems, measured by easily accessible means, are taken as diagnostic parameters – the voltage during the transition of the preparatory stage of the discharges to the spark stage and the voltage on the capacitor after the discharge in the semiconductor spark plug goes out. The laws of distribution of diagnostic quantities were experimentally determined, using methods of probability theory, expressions were obtained for the numerical characteristics of discharge parameters as a function of diagnostic quantities and characteristics of the elements of discharge circuits of ignition systems.

SPECTROSCOPY OF UNDERWATER DISCHARGE PLASMA WITH COPPER AND MOLYBDENUM VAPOUR ADMIXTURES

This work is devoted to the investigation of plasma parameters (excitation temperature and electron density) of the underwater discharge between two types of metal granules, in particular: between single-component granules of copper or molybdenum, copperized molybdenum, and both copper and molybdenum with a volume ratio of 50%. Optical emission spectroscopy was used to study such plasma of underwater spark discharges between different types of granules. Namely, the excitation temperature was determined by the Boltzmann plot technique, and the electron density was obtained from the width of the spectral lines of hydrogen and individual lines of metal atoms, assuming that the Stark effect is the dominant mechanism of roadening.

Reduced-Graphene-Oxide-Based Thin Films: An Alternative Coating for Harsh Space Environments.

Polymeric materials are commonly used as the outermost layer in spacecraft passive thermal control. However, in geostationary earth orbit environments, the polymeric layer is susceptible to environmental hazards, particularly electrostatic charges. In this study, we develop a graphene-based coating on a polymeric polyimide (Kapton®) and discuss its suitability in simulated harsh space environments for electrostatic dissipation. An about 80-100 nm thick conducting reduced graphene oxide (rGO) coating was developed on Kapton® by a simple and cost-effective spray technique while ensuring minimal variation in the thermo-optical properties and hence the equilibrium temperature. The spaceworthiness and stability of the coating were evaluated through simulated space environment tests, including thermal cycling, thermal vacuum, relative humidity, adhesion, and aging tests. Structural, optical, and electrical properties were found to be preserved after spaceworthiness tests, demonstrating the durability of the coating in harsh space environments. Furthermore, field emission scanning electron microscopy demonstrated significant electron charging on uncoated Kapton®, with a gradual reduction in charge buildup for GO-coated Kapton®, and almost negligible charging on rGO-coated Kapton® when subjected to electron bombardment at 10, 15, and 20 kV. Kelvin probe force microscopy further confirmed the enhanced electrostatic dissipative properties, showing a notable decrease in surface potential from 300 mV for uncoated Kapton® to 60 mV for rGO-coated Kapton®. These findings suggest that the developed graphene-based coating holds promise as a space-survivable solution for electrostatic dissipation in a spacecraft.

Electrostatic discharge protection of low-voltage circuits by forward characteristics of wide bandgap semiconductor Schottky barrier diodes

Abstract As a component protecting low-voltage (1–3 V) circuits against disturbance pulses such as electro-static discharge, we propose the application of the forward characteristics of wide bandgap semiconductor Schottky barrier diodes (SBDs). This concept was verified with β-Ga2O3-SBDs, which successfully kept the line voltage to 2.2–4.2 V for an input pulse voltage of 5–70 V with a rise time of less than 1 ns. This indicates that it is applicable for protection against nanosecond-level disturbance pulses.

Saccharomyces cerevisiae inactivation during water disinfection by underwater plasma bubbles: Preferential reactive species production and subcellular mechanisms.

The escalating challenges posed by water resource contamination, especially exacerbated by health concerns associated with microbial fungi threats, necessitate advanced disinfection technologies. Within this context, non-thermal plasma generated within bubble column reactors emerges as a promising antifungal strategy. The effects of direct plasma bubbles within different discharge modes and thus-produced plasma activated water (PAW) on the inactivation of Saccharomyces cerevisiae are investigated. Results show that plasma bubbles generated by dielectric barrier discharge (DBD) mode can effectively inactivate yeast cells (∼4.44 logs reduction) within 1 min, outperforming the spark discharge (SD). In this case, SD can cause a significant portion of cell necrosis, possibly due to the high electric field at the bubble interface. In PAW, DBD and SD produce different dominant long-lived oxygen and nitrogen species, while the crucial short-lived species in yeast apoptosis are both attributed to the singlet oxygen (1O2) as confirmed by scavenger tests. The detection of intracellular reactive oxygen species and antioxidant enzymes further illustrates the role of PAW in triggering apoptosis. Overall, this study demonstrates the discharge mode-dependent modulation of reactive species chemistry in plasma-liquid interactions and provides new insights into the subcellular mechanism of plasma-enabled yeast inactivation for water resource decontamination.

Additive Manufacturing of Polylactic Acid for Electrostatic Discharge Materials Application

Abstract The aim of this research work is to fabricate Electrostatic Discharge (ESD) compliant material utilizing Fused Deposition Modelling. FDM technique was utilized to fabricate ESD-compliant material. Polylactic acid (PLA) was chosen as the main material and blended with the conductive filler Carbon Black (CB) N550. Various CB compositions, ranging from 3-10wt% of Carbon Black N550, were mixed with PLA through a dry blending process for 24 hours at 40 rpm. The resulting material mixture was subsequently extruded into filaments using the 3Devo filament maker. CAD design and Ultimaker Cura slicer were utilized to construct the final product design and printing was carried out using Creality CR-6 SE. ESD test results showed that filament composition consisting of 97wt% PLA and 3wt% Carbon Black N550 achieved the desired ESD characteristics within the specified range. Furthermore, the mechanical properties of this selected blend demonstrated enhanced tensile strength and aligning well with its morphological behavior.

Lightning-Driven Pyrite Oxidation Under Archean Atmosphere Conditions.

Oxidative weathering is a major source of bio-essential micronutrients on Earth today; however, this flux would have been muted on the early Earth or on Mars, where atmospheric O2(g) levels were very low. Here, we explore the hypothesis that nitrogen oxides generated by lightning in an anoxic atmosphere could have elevated pyrite oxidation levels under otherwise anoxic conditions. We performed spark discharge experiments in the presence of pyrite powder and three different gas mixtures, including 80% N2(g) with 20% CO2(g), 95% N2(g) with 5% CO2(g), and modern air. Experiments were run for 30 min, and we tracked the production of NO(g), dissolved nitrate and nitrite, pH, dissolved sulfate, and total dissolved iron. Our results reveal increasing production of nitrogen oxides with increasing CO2(g) and O2(g) levels, which is consistent with previous studies. Dissolved iron and sulfate also increase, indicating that the nitrogen oxides are able to oxidize pyrite abiotically. Extrapolating these data to global conditions suggests that this mechanism was probably insignificant on a global scale on the early Earth; however, in thunderstorm-prone areas, such as in the modern tropics where lightning rates may locally be over 10 times above the global average, lightning could have rivalled abiotic pyrite oxidation by Archean O2 levels. The lightning contribution would have been highest during time periods with elevated CO2(g), which makes it a potentially important contributor to local release of sulphur, iron, and bio-essential micronutrients on prebiotic land surfaces or on other planets with anoxic CO2-rich atmospheres.

Surface Charging Analysis of Ariel Spacecraft in L2-Relevant Space Plasma Environment and GEO Early Transfer Orbit

Ariel (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) is the ESA Cosmic Vision M4 mission, selected in March 2018 and officially adopted in November 2020, whose launch is scheduled by 2029. It aims at characterizing the atmospheres of hundreds of exoplanets orbiting nearby stars by low-resolution primary and secondary transit spectroscopy. The Ariel spacecraft’s operational orbit is baselined as a large-amplitude, eclipse-free halo orbit around the second Lagrangian (L2) point, a virtual point located at about 1.5 million km from the Earth in the anti-Sun direction, as it offers the possibility of long uninterrupted observations in a fairly stable radiative and thermo-mechanical environment. A direct escape injection with a single passage through the Van Allen radiation belts is foreseen. During both the injection trajectory and the final orbit around L2, Ariel will be immersed in and interact with Sun radiation and the plasma environment. These interactions usually result in the accumulation of net electrostatic charge on the external surfaces of the spacecraft, leading to a potentially hazardous configuration for the nominal operation and survivability of the Ariel platform and its payload, as it may induce harmful electrostatic discharges (ESDs). This work presents the latest results collected from surface charging analyses conducted using the SPIS tool of the European SPINE community along the GEO insertion orbit segment and operational orbit.