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This study investigates discharge phenomena in suspended droplets using needle–needle electrodes. By employing ultrasonic suspension technology for noncontact droplet suspension and high‐speed cameras for capturing time‐resolved discharge images, the study examines the impact of droplets on discharge characteristics and morphology. Results show that droplets alter the electric field distribution, affecting discharge paths. Low‐conductivity droplets hinder discharge, causing deflection or changes in the discharge channel, whereas high‐conductivity droplets act as suspended electrodes, facilitating discharge channel formation, reducing breakdown voltage and shortening the establishment time. Droplets transition from ellipsoid to flat and back during discharge, with high‐conductivity droplets potentially undergoing liquid explosion. These findings are crucial for designing high‐voltage equipment in liquid‐contaminated environments. [ABSTRACT FROM AUTHOR]

Polyvinyl butyral (PVB) integrated with varying compositions of potassium chloride (KCl) was prepared through a solution-cast method in methanol, forming a PVB-based electrolyte film for solid-state potassium batteries. The incorporation of KCl into PVB matrix significantly altered the composite electrolyte film's structural intricacies, bandgap modulation, thermal stability and facilitated functional group identification. Furthermore, the ionic conductivity of the PVB polymer electrolyte exhibited an initial enhancement followed by a subsequent reduction with the escalating ratio of KCl. Specifically, at 80 wt% PVB and 20 wt% KCl, its ionic conductivity reached a value of 1.87 × 10−5 S cm−1 at room temperature and 9.61 × 10−5 S cm−1 at 303 K temperature. The ion transference number, which denotes the relative ease with which potassium ions migrate within the PVB polymer-complexed electrolyte, was determined to be 0.98. Discharge tests on the cell, under 1.2 µA current and 2.1 V at room temperature, displayed an initial 9.16 µA h−1 discharge capacity. [ABSTRACT FROM AUTHOR]

Aiming at the characteristics of low relative load capacity and small volume capacity of helicopter platform, and to achieve the purpose of efficient pumping of airborne pulse laser media, an integrated structural design method was adopted to design an efficient pulse power supply system that provides pumping energy for pulse xenon lamps of podded lamp-pumping solid-state laser. Theoretical analysis and experimental verification were conducted on the discharge characteristics and device parameters of xenon lamps, and the key device parameters of discharge main circuit of xenon lamp were obtained. A principle prototype was trial-produced, and joint debugging experiments were conducted. The results show that the actual test data are basically consistent with the theoretical data, and the discharge loop parameters of the pulse power supply system are designed reasonably. The total mass of the power supply system is about 48 kg, the capacitor charging time is 3.76 s, the peak discharge-current of xenon lamp is 3.6 kA, and the pulse width is 1.06 ms, respectively. After adopting the integrated structural design method, the volume and weight of the pulse power supply system can meet the requirements of the airborne platform, verifying the feasibility of the key technology. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-voltage heat release from batteries can cause safety issues for electric vehicles. Relevant scientific research work is carried out in the laboratory. The battery safety of laboratory experiments should not be underestimated. In order to evaluate the safety performance of batteries in the laboratory testing of driving conditions of electric vehicles, this paper simulated and compared the discharge characteristics of two common batteries (lithium iron phosphate (LFP) battery and nickel–cobalt–manganese (NCM) ternary lithium battery) in three different operating conditions. The operating conditions are the NEDC (New European Driving Cycle), WLTP (World Light Vehicle Test Procedure) and CLTC-P (China light vehicle test cycle) for normal driving of electric vehicles. LFP batteries have a higher maximum voltage and lower minimum voltage under the same initial voltage conditions, with a maximum voltage difference variation of 11 V. The maximum current of WLTP is significantly higher than NEDC and CLTC-P operating conditions (>20 A). Low current discharge conditions should be emulated in teaching simulation and experiments for safety reasons. The simulation data showed that the LFP battery had good performance in maintaining the voltage plateau and discharge voltage stability, while the NCM battery had excellent energy density and long-term endurance. [ABSTRACT FROM AUTHOR]

A touchable plasma device based on coplanar dielectric barrier discharge (CDBD) is designed for hand hygiene. The biological safety is evaluated from the aspects of electrical and thermal properties. The peak value of current through the human body (~3.5 mA) and the highest device surface temperature (~40°C) are lower than the threshold of perception current and thermal damage temperature, respectively. The typical bacteria that are present on our hands in daily life Escherichia coli and Staphylococcus aureus are selected to verify the sterilization performance of the device. The results of human contact safety evaluation and sterilization test have demonstrated that this proposed CDBD device is reliable and user‐friendly for applications in hand hygiene. [ABSTRACT FROM AUTHOR]

The discharge of the zinc–perchloric acid–lead dioxide electrochemical system at temperatures from –50 to +50°C was studied. Zinc coatings, including those subjected to chromate passivation, can be used as anode materials for fast-activated reserve chemical power sources. The tests of pilot batches confirmed that the power sources met the activation time requirements (no more than 50 ms). The power sources of the given system are characterized by increased discharge voltage (the maximum voltage of one cell is 2.12–2.44 V) compared with that of the lead–perchloric acid–lead dioxide system (1.50–1.86 V). The disadvantages of the zinc–perchloric acid–lead dioxide system were revealed: instability of discharge characteristics and possible cell polarity reversal as a result of side reactions, which may have a significant negative impact on the reliability of reserve power sources. [ABSTRACT FROM AUTHOR]

Vanadium redox flow batteries are promising energy storage devices and are already ahead of lead–acid batteries in terms of installed capacity in energy systems due to their long service life and possibility of recycling. One of the crucial tasks today is the development of models for assessing battery performance and its residual resource based on the battery's present state. A promising method for estimating battery capacity is based on analyzing present voltage and current values under various load conditions. This paper analyzes the discharge characteristics of a 10 kW all-vanadium redox flow battery at fixed load powers from 6 to 12 kW. A linear dependence of operating voltage and initial discharge voltage on load power is established. It is also determined that the slope of the discharge curve linear section does not increase linearly in absolute value, and the Box–Lucas model can be used to describe it. Models for predicting current VRFB capacity based on different curve fitting functions are proposed. These models can be used to roughly estimate battery capacity at different load powers. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

RELEVANCE. Suspended insulators, the technical condition of which largely determines the reliability of power supply to consumers of different categories, are one of the most damaged elements of overhead power transmission lines [1-2]. This is primarily due to the fact that during their operation, insulators are exposed to various climatic conditions that have a direct impact on their insulating properties. Moreover, precipitation, such as rain, fog or dew, has the greatest impact precisely in combination with various solid, liquid and gaseous particles deposited on the insulator surface from the air, and forming a layer of surface contamination. Wetting this layer increases the electrical conductivity of the entire overhead line insulation structure and reduces its insulating capacity. Study of influence of dampening of contaminated surface of suspended insulation on their discharge characteristics is an urgent scientific task. The solution of this task enables to develop the existing understanding of the mechanisms of formation and development of discharges on the contaminated and wetted surface of insulation and to formulate the appropriate diagnostic attributes applicable to control the condition of the overhead power line insulators. OBJECTIVE. To carry out laboratory research aimed at studying the behavior of suspended high-voltage polymer insulators of overhead power lines when they are moistened. To formulate appropriate diagnostic attributes applicable for control of condition of suspended insulators of overhead power lines during their operation. METHODS. At the solution of the posed problem experimental methods of research, consisting in simulation of work of the contaminated polymeric insulator in the atmosphere of a pure fog with application of the special experimental installation developed by the authors of this article were applied. RESULTS. As a result of laboratory research, by continuous registration of leakage current values, as well as signals coming from the remote sensor, characteristic features of contaminated insulator humidification were revealed, which can be used as diagnostic signs in the process of their operation.

As converter stations are increasingly constructed at high altitudes, how to reasonably select the minimum air spacing of converter station substation equipment has become an important issue for DC power transmission at high altitudes. In order to study the influence of air environment on switching impulse discharge characteristics of air gap at high altitudes, this paper conducts switching impulse discharge tests on 1 m rod-plate air gap under different air pressure, temperature, and humidity conditions, investigates switching impulse discharge characteristics of rod-plate air gap at high altitude, and compares and analyses differences in correction results of various discharge voltage correction methods. Studies have shown that air pressure, temperature, and humidity have an effect on air gap discharge voltage. Meanwhile, based on different atmospheric parameters, correction formulas are obtained for 1m rod-plate air gap discharge voltage, and the elevation correction coefficients of 1m rod-plate air gap at each altitude was obtained. The results of the study provide a reference for external insulation of equipment and its insulation fit in converter stations at high altitude.

In this study, a support vector machine (SVM) and three optimization algorithms are used to develop a discharge coefficient (Cd) prediction model for the semi-circular side weir (SCSW). After that, we derived the input and output parameters of the model by dimensionless analysis as the ratio of the flow depth at the weir crest point upstream to the diameter (h1/D), the ratio of main channel width to diameter (B/D), the ratio of side weir height to diameter (P/D), upstream of side weir Froude number (Fr), and Cd. The sensitivity coefficients for dimensionless parameters to Cd were calculated based on Sobol's method. The research shows that SVM and Genetic Algorithm (GA-SVM) have high prediction accuracy and generalization ability; the average error and maximum error were 0.08 and 2.47%, respectively, which were about 95.72 and 60.86% lower compared with the traditional empirical model. The first-order sensitivity coefficients S1 and global sensitivity coefficients Si of h1/D, B/D, P/D, and Fr were 0.35, 0.07, 0.13, and 0.02; 0.63, 0.25, 0.30, and 0.32, respectively. h1/D has a significant effect on Cd. In particular, when h1/D < 0.24 and 0.48 < Fr < 0.58, 0.67 < Fr < 0.72, the discharge capacity of the SCSW is relatively large. HIGHLIGHTS We developed an effective and high-accuracy model for predicting the Cd of SCSW.; The importance of dimensionless parameters on Cd was quantified by Sobol's method.; It explored the flow characteristics of semi-circular side weir.;

In order to improve the concentration and output of ozone produced by dielectric barrier discharge, the characteristics of ozone produced by dielectric barrier discharge under different square wave pulse modes are studied in this study. The discharge characteristics of the system are analyzed, the discharge power of the system is calculated, and the concentration and output of ozone produced under different polarity, frequency and pulse width are studied. The results are analyzed and discussed. The results show that the ozone concentration is the highest (8.8 g·Nm-3) when positive and negative square wave pulses are applied, while the ozone yield is the highest (55 g·kWh-1) when positive square wave pulses are applied. With the increase of the frequency, the ozone concentration and production show a trend of first increasing and then decreasing. When the discharge frequency is 1 kHz, the ozone concentration is the highest, and when the discharge frequency is 1.5 kHz, the ozone production is the highest. Under the condition that other parameters are fixed, the ozone concentration increases slowly with the increase of pulse width, and the output of ozone basically remains unchanged. [ABSTRACT FROM AUTHOR]

Gas–liquid discharge coupling with photocatalysts is an effective approach to enhance the chemical activity of plasma treated liquid. However, the incomplete understanding of the discharge characteristics with the addition of photocatalysts remain. The characteristics of pulsed gas–liquid discharge combining TiO2 or WO3 are studied in this work to address this issue. Results indicate that the addition of photocatalysts significantly promote the discharge, as evidenced by the diagnosis of discharge current, optical emission spectra, concentrations of aqueous species and solution properties. Specifically, the addition of catalysts enhances the discharge current and enrich the emission spectrum. The atomic emission lines O (3p–3s), N (3p–3s) and Hα were also observed with the addition of TiO2, followed by higher content of reactive species in the solution. However, the addition of catalysts makes the discharge more unstable. This study contributes to an improved understanding of the mechanism of gas–liquid discharge coupled with photocatalysts for the improvement in applications. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD), a non-thermal plasma technology, has a wide range of environmental applications. In this study, TiO2, SiO2, and Al2O3 were coated on the surface of a quartz dielectric using a dip-coating method. The catalyst coating coatings effectively improved the local discharge intensity, thus enhancing the generation of reactive species. After discharge by the DBD system, the O atom in the middle of TiO2 crystal is replaced by N atom doping, and the Al = O and Al OH groups on the surface of Al2O3 increase. All Catalyst coating surfaces contained a small number of hydroxyl groups. TiO2 and Al2O3 surfaces had fewer oxygen vacancies. thus making O3 synthesis dominant at the gas–solid interface. [ABSTRACT FROM AUTHOR]

The reasonable geometry design of non-thermal plasma (NTP) reactor is significant for its performance. However, optimizing the reactor structure has received insufficient attention in the studies on removing volatile organic compounds by NTP. Several dielectric barrier discharge (DBD) reactors with various barrier thicknesses and discharge gaps were designed, and their discharge characteristics and toluene degradation performance were explored comprehensively. The number and intensity of current pulses, discharge power, emission spectrum intensity and gas temperature of the DBD reactors increased as barrier thickness decreased. The toluene removal efficiency and mineralization rate increased from 23.2–87.1% and 5.3–27.9% to 81.7–100% and 15.9–51.3%, respectively, when the barrier thickness reduced from 3 to 1 mm. With the increase of discharge gap, the breakdown voltage, discharge power, gas temperature and residence time increased, while the discharge intensity decreased. The reactor with the smallest discharge gap (3.5 mm) exhibited the highest toluene removal efficiency (78.4–100%), mineralization rate (15.6–40.9%) and energy yield (8.4–18.7 g/kWh). Finally, the toluene degradation pathways were proposed based on the detected organic intermediates. The findings can provide critical guidance for designing and optimizing of DBD reactor structures. [ABSTRACT FROM AUTHOR]

The article presents a universal combined model of the electrochemical battery, built on the basis of the modified Shepherd equation and the kinetic model. The proposed model provides the adequate mapping of the basic characteristics of the battery in operating mode, taking into account the physical constraints of the capacity available. The results of verification of the developed mathematical model using lead-acid and lithium-iron-phosphate batteries are presented. These results prove its higher accuracy in comparison with the basic model of MATLAB/Simulink electrochemical battery.

Storm-drain inlets can lessen surface runoff and are essential for managing urban flooding. To fully grasp the storm-drain inlet discharge characteristics, a computational fluid dynamics (CFD) method was utilised to research. In this study, the discharge characteristics of 36 groups of storm-drain inlets with various water depths and flow velocities were simulated separately. This paper systematically analysed the distribution characteristics of flow patterns, streamlines and velocities of storm-drain inlets. The findings indicate that: the distribution of streamlines and the shape of the free water surface within the storm-drain inlet change significantly with increasing incoming water depth; the flow pattern in the vicinity of rainwater wells changes from the free weir flow to the submerged weir flow; the free water surface of the storm-drain inlet transitions from the state of being partially to entirely covered by water flow. The empirical formula between the discharge coefficient of the storm-drain inlet and the Froude number was constructed by dimensional analysis with a high correlation coefficient. And compared with other empirical formulas, the formula considers the effects of different factors on the discharge capacity of storm-drain inlets in a relatively comprehensive way. This research's results help deepen the awareness of the discharge process at storm-drain inlets and have implications for guiding municipal flooding management. [ABSTRACT FROM AUTHOR]

High-voltage heat release from batteries can cause safety issues for electric vehicles. Relevant scientific research work is carried out in the laboratory. The battery safety of laboratory experiments should not be underestimated. In order to evaluate the safety performance of batteries in the laboratory testing of driving conditions of electric vehicles, this paper simulated and compared the discharge characteristics of two common batteries (lithium iron phosphate (LFP) battery and nickel–cobalt–manganese (NCM) ternary lithium battery) in three different operating conditions. The operating conditions are the NEDC (New European Driving Cycle), WLTP (World Light Vehicle Test Procedure) and CLTC-P (China light vehicle test cycle) for normal driving of electric vehicles. LFP batteries have a higher maximum voltage and lower minimum voltage under the same initial voltage conditions, with a maximum voltage difference variation of 11 V. The maximum current of WLTP is significantly higher than NEDC and CLTC-P operating conditions (>20 A). Low current discharge conditions should be emulated in teaching simulation and experiments for safety reasons. The simulation data showed that the LFP battery had good performance in maintaining the voltage plateau and discharge voltage stability, while the NCM battery had excellent energy density and long-term endurance.

Vanadium redox flow batteries are promising energy storage devices and are already ahead of lead–acid batteries in terms of installed capacity in energy systems due to their long service life and possibility of recycling. One of the crucial tasks today is the development of models for assessing battery performance and its residual resource based on the battery’s present state. A promising method for estimating battery capacity is based on analyzing present voltage and current values under various load conditions. This paper analyzes the discharge characteristics of a 10 kW all-vanadium redox flow battery at fixed load powers from 6 to 12 kW. A linear dependence of operating voltage and initial discharge voltage on load power is established. It is also determined that the slope of the discharge curve linear section does not increase linearly in absolute value, and the Box–Lucas model can be used to describe it. Models for predicting current VRFB capacity based on different curve fitting functions are proposed. These models can be used to roughly estimate battery capacity at different load powers.

To solve the dust pollution problem, this paper proposes a new grounded electrode atomized corona discharge coupled with a screen dust collection pole dust collector (ASEP). The discharge characteristics of the wire-barrel electrode (with an aperture of 0 mm) and the wire-mesh barrel electrode (with screen apertures of 1, 2, and 3 mm, respectively) were compared, and the factors influencing the dust removal efficiency were investigated. In the case of grounded atomized negative corona discharge, the discharge characteristics of the wire-barrel electrode (aperture of 0 mm) and wire-mesh barrel electrode (screen aperture of 1 mm) were compared, and the influencing factors of the dust removal efficiency were studied. In the case of grounded electrode atomization negative corona discharge, it is found that the wire-mesh cylinder electrode (screen aperture of 1 mm) has the best dust removal efficiency, and the total charge of the grounded electrode atomization corona discharge of the wire-mesh cylinder structure is dominated by air ionization charge, and the charged liquid droplets only play the role of cleaning.

For particles produced in the governance industry, expounds and summarizes the mechanical dust removal，bag dust removal, wet dust removal, electrostatic dust removal process characteristics, this paper introduces the typical technology research background and application value of electrostatic dust removal technology process principle and research progress, summarizes the factors aftecting electrostatic technology discharge characteristics, highlights the discharge electrode material and dust specific resistance on dust removal efficiency, points out the possible problems of electrostatic precipitator. [ABSTRACT FROM AUTHOR]

In recent years, a large number of countries have connected and distributed photovoltaics in remote rural areas, aiming to promote the use of clean energy in rural areas. The solar energy that is not used in time needs to be discarded, resulting in a large amount of wasted energy. Rural areas are closely related to agricultural production, and solar energy can be used for agricultural nitrogen fixation to supplement the nitrogen needed by crops and effectively use the upcoming waste of solar energy. A photovoltaic-driven plasma reactor for nitrogen fixation in agriculture was designed in this study. The air inlet and outlet holes are arranged above and below the reactor to facilitate air entry and directly interact with the gliding arc generated at the bottom of the electrode to achieve atmospheric nitrogen fixation in agriculture. The characteristics of gliding arc development in the process of nitrogen fixation in agriculture were studied experimentally. There are two discharge modes of the gliding arc discharge: one is steady arc gliding mode (A-G Mode), and the other is breakdown gliding mode (B-G Mode). By collecting discharge signals, different discharge modes of gliding arc discharge were analyzed, and the effect of the air flow rate on the discharge period and discharge mode ratio distribution is discussed. The effects of the air flow rate on the yield, specific energy input, and energy consumption in plasma agriculture were studied. The experimental results show that with an increase in the air flow rate, the B-G mode takes up a larger proportion and the gliding arc discharge period is shortened. However, the higher the proportion of the B-G mode, the more unfavorable the production of nitrogen oxides. Although the nitrogen oxides generated by the system are not particularly excellent compared with the Haber-Bosch ammonia process (H-B process), the access to distributed photovoltaic roofs in rural and remote areas can effectively use available resources like water, air, and solar, and avoid energy waste in areas where wind and solar are abandoned. [ABSTRACT FROM AUTHOR]

There are numerous scientific and engineering fields where the surface dielectric barrier discharge driven by nanosecond pulses (NS-SDBD) has important applications. To improve its performance, more research is still needed on the effects of electrical parameters on the NS-SDBD actuator's discharge characteristics. In this study, a two-dimensional numerical model based on 13 discharge particle chemical processes was constructed using a numerical simulation approach, producing findings for the NS-SDBD actuator's voltage–current (V-A) characteristics, discharge profile, and spectrum analysis. Additionally, a comprehensive investigation into the trends and underlying mechanisms of the effects of the voltage amplitude, pulse width, rise time, and fall time parameters on the discharge behavior of the NS-SDBD actuator was carried out. The results show that higher voltage amplitudes increase the maximum current and electron density, which enhances the plasma excitation effect. The peak power deposition during the second discharge is also raised by longer pulse widths and rise times, whereas the total power deposition during the second discharge is decreased by longer fall times. [ABSTRACT FROM AUTHOR]

In order to better meet the needs of high-power chemical power sources for aviation, military and energy devices, the LTT65 series battery was optimized by controlling the other parameters of the original battery and made the internal particles smaller, so that the discharge rate of the optimized battery can be improved. For the improved battery, firstly the discharge performance of the battery was tested to obtain the specific value of the depth of discharge, and then the internal resistance was tested and calculated by the hybrid pulse power characteristic (HPPC) method according to the voltage recovery problem after the battery was discharged. The results show that the internal resistance of the battery decreases with the increase of the discharge rate in the high state of charge (SOC) state, and the internal resistance of the battery increases in the lower SOC state, showing a certain complex trend. Finally, the temperature rise of the battery was analyzed in this multiplier state, and it is concluded that the battery temperature will have an inflection point with the increase of the battery discharge rate. The temperature inflection point of the battery occurs at 45 ℃, with a maximum temperature value of 63 ℃ and a temperature rise value of 38 ℃, then according to the experimental results, the temperature rise, thermal power and other parameters of the battery at different rates were measured, the exothermic characteristics of the battery were studied as a whole. [ABSTRACT FROM AUTHOR]

Aiming at the discharge problem of inductively coupled plasma (ICP), a closed wave-transmitting cavi-ty configuration is designed, the fluid mechanics model of ICP is established, and the multi physical simulation software COMSOL is used for three-dimensional simulation research. The variation laws of typical parameters such as electron density, electron temperature and plasma potential with time in the discharge process are analyzed. On this basis, the power of radio frequency power supply, the air pressure in the cavity and other conditions are changed to obtain the parameter range and spatial gradient distribution of ICP. The results show that the discharge power mainly affects the numerical range of plasma parameters, and the change of air pressure has an effect on the numerical value and spatial distribution of plasma parameters. When the power of radio frequency power supply increases from 100 W to 300 W, the peak electron density increases from 2.54×1017 m-3 to 5.68×1017 m-3, and the electric potential induced in the heating zone and the corresponding electron temperature decrease slightly after the reaction is stable. Increasing the air pressure in the cavity within a certain range will significantly increase the electron density. The air pressure increases from 10 Pa to 30 Pa, and the electron density increases from 9.12×1017 m-3 to 3.62×1018 m-3. However, the uniformity of plasma parameter distribution will deteriorate if the air pressure is too high.

Non-equilibrium plasma has been proven to expand ignition limits and enhance combustion. This paper uses high-voltage nanosecond pulsed discharge (NPD) to generate non-equilibrium plasma and experimentally studies the discharge characteristics at different parameters in a constant-volume combustion bomb. NPD is used to ignite the methane-air mixture, and the effects of pulse power output voltage and pulse interval (PI) on ignition and combustion processes are studied. In addition, the minimum ignition energy (MIE) at different ignition methods (Transistor coil ignition (TCI) and NPD) is also studied. The results show that the first pulse of NPD discharge has a higher breakdown voltage and discharge energy when using multi-pulse discharge. After the second pulse, the highest breakdown voltage and current tend to stabilize, and the discharge energy remains unchanged. As the PI increases, the breakdown peak voltage and the peak current increase slightly. The study on the MIE of NPD shows that at different mixture concentrations, the MIE of NPD is smaller than that of TCI, and NPD can expand the lean burn limit. An increase in initial temperature can significantly reduce MIE. In addition, when the discharge energy is near the MIE, the combustion stability begins to decrease, and the combustion cycle fluctuates wildly. When the ignition energy is increased, the stability improves, and the combustion fluctuation rate can be maintained within 5%. [Display omitted] • The breakdown voltage and current characteristics of NPD at different discharge parameters are investigated. • Minimum ignition energy is studied for different ignition methods. • At the same parameters, the discharge energy of the hundred-nanosecond pulse is higher than that of the ten-nanosecond pulse. • At different mixture concentrations, the MIE of NPD is smaller than that of TCI. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are one of the most popular and efficient energy storage devices. In this paper, the characteristics of high-capacity lithium-iron-phosphate batteries during the impulse and long-term operation modes of batteries with different levels of the discharge current are considered. A modified DP-model is proposed. The novelty of the model is the possibility to calculate the activation polarization parameters for different discharge currents. The state of charge is estimated using a high-order polynomial. Based on the developed model, transient processes with rapid load changes and the dependence of the battery voltage on the state of charge were obtained. Here, the model is intended to be used for the design of energy storage systems. The results showed that the DP-model is reliable under the tested conditions and can be used for the considered application. [ABSTRACT FROM AUTHOR]

Liquid‐phase discharge has the advantages of high plasma density, simultaneous generation of multiple physical and chemical effects, and high gas‐liquid mass transfer efficiency. However, the large‐capacity treatment of liquid by plasma has always been a research difficulty. In this study, liquid‐phase continuous arc (LCA) discharge plasma is realized for the first time, which can quickly propagate for a long distance in liquid. To better understand this new type of liquid‐phase discharge, the time‐space characteristics, electrical characteristics, optical characteristics and particle characteristics of the LCA discharge plasma are diagnosed. The results show that the LCA discharge plasma can achieve a rapid propagation over 1 m in the liquid, and the propagation time is on the order of milliseconds. Meanwhile, the discharge can directly generate a variety of active species (·OH, ·O, ·H, H2O2) in the liquid, which can be continuously produced as the plasma moves. The LCA discharge plasma has good application prospects in water treatment, energy conversion, and so on. [ABSTRACT FROM AUTHOR]

Under the condition of DC discharge, a method to form a low-temperature plasma jet in atmospheric pressure air is proposed. By analyzing the electric field distribution characteristics and discharge phenomenon of the aluminum foil needle electrode, it is found that the existence of the upper hemispherical aluminum foil can increase the electric field at the tip of the needle electrode, thereby increasing the difference of the electric field strength between the needle electrode tip and the lateral side of the needle electrode. Under the action of the gas flow, the discharge phenomenon generated by the double-needle electrode forms a tip arc that distorts the electric field in the front space, thereby forming a plasma jet extending axially forward in the outer space of the gas nozzle. By further optimizing the structure of the double-needle electrode, it is found that the plasma jet can form the spatial electric field with transitive change in the formation process of the plasma jet, which can form a plasma jet that exceeds the right ground electrode. The self-pulse discharge formed by the inter-electrode arc can provide more seed electrons during the formation of the plasma jet. Finally, a longer, higher density atmospheric pressure air low temperature plasma jet is formed without airflow. [ABSTRACT FROM AUTHOR]

The rapidly growing commercialization of electric vehicles demands higher capacity lithium-ion batteries with higher heat generation which degrades the lifespan and performance of batteries. The currently widely used indirect liquid cooling imposes disadvantages of the higher thermal resistance and coolant leakage which has diverted the attention to the direct liquid cooling for the thermal management of batteries. The present study conducts the experimental investigation on discharge and heat transfer characteristics of lithium-ion battery with direct liquid cooling for the thermal management. The 18,650 lithium-ion cylindrical battery pack is immersed symmetrically in dielectric fluid. The discharge voltage and capacity, maximum temperature, temperature difference, average temperature, heat absorbed, and heat transfer coefficient are investigated under various conditions of discharge rates, inlet temperatures, and volume flow rates of coolant. The operating voltage and discharge capacity are decreasing with increase in the volume flow rate and decrease in the inlet temperature for all discharge rates. At the higher discharge rate of 4C, the lowest battery maximum temperatures of 60.2 °C and 44.6 °C and the highest heat transfer coefficients of 2884.25 W/m2-K and 2290.19 W/m2-K are reported for the highest volume flow rate of 1000 mLPM and the lowest inlet temperature of 15 °C, respectively. [ABSTRACT FROM AUTHOR]

Gas-insulated switchgear (GIS) might withstand ac/lightning impulse (LI) superimposed voltage caused by lightning intrusion or switching operation during operation. When there are insulation defects, the breakdown probability is greatly increased, which threatens the safety of GIS and needs to be further studied. In this study, the discharge characteristics of two typical insulation defects, including a metallic protrusion on bus bar and foreign matter attached to insulator, under ac/LI superimposed voltage were studied, and the influence of superimposed phase, polarity, and ratio was investigated. It was found that, under a quasi-uniform electric field, the superimposed breakdown voltage (${U}_{s}$) was the same as the LI breakdown voltage (${U}_{\text {LI}}$). However, when there were insulation defects, ${U}_{s}$ was significantly affected by the superimposed phase and polarity. For the metallic protrusion, the most critical condition was an −LI superimposed at $\varphi =90$ , with ${U}_{s}$ decreasing by 11% relative to ${U}_{\text {LI}}$. For the metallic particle attached to insulator, when an +LI was superimposed at $\varphi = 0^{\circ }$ or −LI at $\varphi = 180^{\circ }$ , ${U}_{s}$ decreased most, by as much as 19.6% relative to ${U}_{\text {LI}}$. Finally, the validation test was performed in a 110-kV GIS with insulation defects and ${U}_{s}$ was 7%–14% lower than ${U}_{\text {LI}}$. The results showed that, under a proper superimposed phase and polarity, ${U}_{s}$ could be significantly lower than ${U}_{\text {LI}}$ of GIS with insulation defects, indicating the great potential of the ac/LI superimposed voltage test for the high-sensitive detection of GIS insulation defects. [ABSTRACT FROM AUTHOR]

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This paper presents the design of a novel atomized corona discharge coupled screen electrode dust collector, which integrates electrostatic capture and wet electrostatic dust removal technologies. The upper part of the dust collector features an atomized corona discharge electrode utilizing a threaded-wire hole design with uniform water distribution. This design effectively addresses the issue of electrode fatness that may arise from uneven distribution of the discharge electrode. In contrast, the lower part of the collector is equipped with four side-by-side silk screen electrodes, which serve to expand the dust collection area, facilitate secondary particle capture, and consequently enhance dust removal efficiency. The study delves into a detailed analysis of the impact of various parameters on discharge characteristics and dust removal efficiency, culminating in the identification of optimal parameters. • A dust removal device combining an atomized corona discharge device and an electrostatic capture device was designed, in which a threaded wire hole electrode was designed to effectively expand the corona discharge area. • The experimental results show that the addition of atomized water does not affect the charging of the particles, and a better discharge and dust removal effect can be obtained at a smaller flow rate (10 mL/min). • The effects of electrode spacing, flow rate and other factors on the dust removal efficiency were investigated, and the optimal dust removal efficiency was 91.56% when the atomized corona discharge device was coupled with metal mesh electrodes, which was significantly improved by 4.42%. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conveyor belt and high-speed camera were used to collect the DTD of particles. • The MFR prediction model was established by fitting the mass with image by ANN. • Calculation of MFI by CNN combined with error correction. • The test results for glass beads and quartz sand were within the tolerance range. A machine vision and neural network-based method for the quantitative detection of hopper discharge characteristics based on the discharge time distribution is proposed. Glass beads and quartz sand were utilized as test objects. The prediction model of the relationship between the particle mass and the pixel value of the image was established by an artificial neural network, and the mass flow rate (MFR) was calculated via image prediction. The average relative errors of the predicted MFR for glass beads and quartz sand were found to be −1.31 % and −2.02 %, respectively. Based on the particle marking method, a convolutional neural network was used to classify the image according to whether there were marked particles in the image, and the mass flow index (MFI) was calculated after error correction. The average relative errors of the predicted MFI values for glass beads and quartz sand were found to be −1.43 % and 0.82 %, respectively. [ABSTRACT FROM AUTHOR]

In order to improve the combustion performance of a ramjet under low temperature and pressure, a gliding arc plasma actuator was designed based on a typical evaporation flameholder. The discharge characteristics, as well as the activating effect of single-channel and three-channel gliding arc plasma under different carrier gas flow rates, were studied. Results show that with the increase in the carrier gas flow rate, the average duration of the gliding arc discharge becomes shorter, while the average power increases, and the specific input energy decreases. Compared with single-channel discharge, three-channel discharge has higher discharge power and energy injection rate, which makes a bigger actuated space. Through gliding arc plasma, the kerosene is cracked and H2, CH4, C2H2, C2H4, C3H6 and other small molecule components are produced. For three-channel gliding arc discharge, the effective cracking rate and the production rate of each component are higher than those of the single-channel discharge; both of them gradually increase with the increase in the carrier gas flow rate. The experiment results indicate that three-channel gliding arc plasma can effectively widen the ignition boundary and improve the combustion efficiency of ramjet combustion. The ignition pressure boundary is expanded from 60 kPa to 50 kPa under 390 K; the combustion efficiency is increased from 76% to 82%. [ABSTRACT FROM AUTHOR]

In this article, we investigate the influence of external discharge conditions on plasma parameters in the plasma discharge chamber of the radome configuration. We designed a conformal cavity and then used the multiphysics simulation software COMSOL to establish a 2-D axisymmetric model for discharge simulation research. In the study, we found that the changes in coil power and pressure have a noticeable effect on the distribution of plasma parameters. First, the maximum electron density, electric potential, and electron temperature are obtained by changing the power of the coil in a certain pressure argon environment. Then, under the condition of constant coil power, the discharge characteristics of plasma are studied by changing the gas pressure in the cavity. The results show that the change of coil power has a significant impact on the parameter distribution of plasma discharge. The greater the coil power, the greater the electron density, and the more concentrated the distribution. At the same time, the potential induced in the heating zone and the corresponding electron temperature decreased after the reaction stabilized. The increase of gas pressure significantly increases the peak value of electron density and changes the parameter distribution of discharge. However, when the argon pressure exceeds a certain threshold, it will no longer have a significant effect on the distribution of discharge parameters. The general conclusion is that the increase of power and argon pressure plays an essential role in improving the electron density distribution. This conclusion has guiding significance for exploring the law of plasma parameter distribution on electromagnetic scattering characteristics. [ABSTRACT FROM AUTHOR]

In order to further explore the discharge characteristics of different shaped particles from the inclined bottom hopper, the discharge of four shaped particles from an inclined bottom rectangular hopper was studied based on the discrete element method (DEM). Non-spherical particles were established based on the multi-spheres method. The effects of geometric parameters, particle properties, and interaction parameters on discharge were investigated. Some interesting results have been found that regular spherical particles are more easily discharged from the hopper, and the time required to empty the hopper is the shortest. The influence of particle shape on discharge takes precedence over that of solid fraction. Both the critical angle (55°) and the correlation between the 2/3 power of the mass discharge rate and the orifice width are independent of the particle shape. Blockage occurs as the angle and/or the ratio of particle size to orifice width increases. The dihedral angle is the key factor affecting the blockage. Compared with spherical particles, non-spherical particles are more prone to blockage and have stronger blockage strength. [ABSTRACT FROM AUTHOR]