Discharge Conditions Research Articles

Growth mechanism of microarc oxide membrane under the distribution law of Si and Zr elements

This study investigated the growth mechanism of microarc oxidation ceramic coatings on AZ91D magnesium alloy by sequentially treating it in silicate and zirconate electrolyte systems. The distribution patterns of Si and Zr elements were examined to understand the growth mechanism. The results showed that the distribution of Si and Zr elements in the SZ ceramic coatings changed with increasing termination voltage of microarc oxidation. The growth mechanism of microarc oxidation ceramic coatings on magnesium alloys involved the reaction between Si and Zr elements from the electrolyte and Mg elements from the substrate to form molten oxides under the high-temperature and high-pressure conditions of microarc oxidation discharge. At lower termination voltages, some of the molten oxides remained near the discharge channels or the film/substrate interface, resulting in inward growth of the ceramic coating. As the termination voltage increased, some of the molten oxides were ejected outward through the discharge channels, facilitating outward growth of the ceramic coating. The inclusion of silicon elements compared to zirconium elements will significantly increase the concentration of oxygen vacancies in the ceramic membrane, enhancing the electrical conductivity of the ceramic membrane while reducing its corrosion resistance.

Analysis on battery thermal management system based on flat heat pipe at high discharging rate

Power batteries are the core power source for electric vehicles. However, battery thermal management technology for electric vehicles will face more severe challenges in the future. Flat heat pipe has gradually received much attention in the field of battery thermal management due to its high heat conduction coefficient and lightweight structure. This paper focuses on the influence of flat heat pipe structural parameters on battery thermo-electrical performance by establishing simulation model of the battery cooling system, which makes contribution to the flat heat pipe structure design on optimizing battery overall performance. Based on the mechanism of working medium flow effect of flat heat pipe on the battery electrochemical heat generation, a coupled model of flat heat pipe-based battery system is established according to the relationship between battery electrochemical heat generation performance and flat heat pipe heat transfer characteristics. The accuracy of system model is further verified by experiment, and the battery thermo-electrical characteristics under different discharging conditions is simulated. The flat heat pipe-based battery thermal management system can effectively reduce the battery maximum temperature while improving the uniformity of battery temperature and state of charge (SOC). The reduction of the vapor chamber thickness causes the uneven distribution of vapor thermal resistance, so the battery maximum temperature and maximum temperature difference will become larger, which will further cause the uneven distribution of battery internal resistance, and this will finally increase the non-uniformity of battery module discharging current distribution. A structural design method of the flat heat pipe-based battery thermal management system is developed with the battery thermo-electrical coupling performance as the design objective and the flat heat pipe structural parameters (total thickness, vapor chamber thickness, total length) as the optimization variables. Compared with the original scheme, the battery maximum temperature can be reduced by 6.4% under transient high-rate discharging conditions with the modified flat heat pipe based on the proposed design method, while the battery maximum temperature and SOC difference can also be reduced by 18.4% and 16.3%, respectively.

Modeling of the multi-cycle deep charge and discharge attenuation mechanism of non-aqueous Li–O2 batteries

Due to the high energy density, non-aqueous lithium-oxygen (Li–O2) batteries attract significant attention. However, batteries' high capacity attenuation rate under deep charge and discharge conditions remains a significant challenge. This paper presents a multi-cycle deep charge and discharge model for non-aqueous lithium-oxygen batteries, which predicts the performance of the battery during multiple deep charge and discharge cycles at high and low discharge-specific capacities. The parameter states during different discharge stages in different discharge cycles are investigated by analyzing the battery's cathode porosity, product volume fraction, and oxygen concentration changes. The study shows that as the number of cycles increases, the deposition of a small number of discharge products in the cathode altered the distribution of the newly generated products, thereby affecting the cathode structure and oxygen transport in the subsequent discharge. Moreover, depositing a small amount of discharge products can result in significant capacity attenuation in the battery. This model can accurately evaluate the deep charge and discharge performance attenuation process of non-aqueous Li–O2 batteries, which helps improve the understanding of the deep discharge attenuation mechanism of non-aqueous Li–O2 batteries.

Big river channel formation and deformation in the intermountain basin (case study of the Yana River within the Kular mountain massif)

The incised pebble-boulder channels of large mountain rivers (including the Yana in its mountainous area), their morphology and history of formation are well studied. However, local conditions within the intermountain depressions lead to the emergence of specific features of the channel development and its morphology — in this case, the formation of finger-shaped meander. The paper analyzes the historical and modern features of the formation of the Yana riverbed in the “Porogi” section located in the depression inside Kular range, and describes the negative impact of channel processes on navigation. Using this case study, we consider the characteristic features of the channel development of a large river under the influence of a complex of factors — the regional geological conditions (which caused active incision of the channel), discharge, and channel sediment composition. Characteristics of lateral migration and curvature development of meander controlled by bedrock and narrowing of the valley are presented. The discharge conditions under which the displacement of riffles is possible are calculated. The forecast of the further channel development and recommendations for sustainable navigation are given.

Regulating sodium deposition by specific surface area composite ratio for anode-free Na metal batteries

Anode-free sodium metal batteries (AFSMBs) have greater potential to be one of the electrochemical storage technology choices for high energy density. However, the anode-free current collector is more likely to grow dendrites than the metal anode. Here we report a transformative structural combination strategy to build an anode-free current collector with an ultraconformal structure between the conducting network and metallic sodium deposition space in anode-free metal batteries. The reversibility of the sodium plating/stripping process is significantly enhanced using this strategy, achieving stable operation for more than 2100 cycles at current density (1 mA cm−2) with 1 mA h cm−2 while maintaining an average coulombic efficiency of 99.5 %. The Na-diffused ZnIn2S4 current collector delivers an excellent maximum current density of 10 mA cm−2. In addition, optimization of the structure in the ZnIn2S4||Na3V2(PO4)3 full cell system leads to the successful realization of high-energy-density anode-free sodium cells. These cells exhibit excellent cycling stability under high-rate discharge conditions (5 C), with a capacity retention rate of 91 % after more than 500 cycles. The study presents a promising strategy for constructing an ultraconformal structural framework for high-performance AFSMBs.

Design of electronic system for 2D hard X-ray spectrum camera on EAST

This paper presents the construction of a electronic system for two-dimensional hard X-ray spectroscopic imaging using CZT(Cadmium Zinc Telluride, CdZnTe) detector on EAST(Experimental Advanced Superconducting Tokamak), designed to measure the spatiotemporal distribution evolution of fast electrons in the energy range of 20 keV-700 keV. The system primarily consists of a two-dimensional array of CZT detector, an observation window, shielding components, front-end electronics system, and a data acquisition system. The two-dimensional array of detector is installed on the horizontal D window of EAST, with an observation range covering the plasma core region. The system achieves a temporal resolution of 2–16 ms and a spatial resolution of 10 cm. Data processing is carried out using FPGA-based (Field Programmable Gate Array) spectral recognition algorithms. Prior to the experiments on EAST, spectrum calibration is conducted using radioactive sources Eu152, Cs137, and Am251. In the 2023 EAST experiments, the system successfully measured the behavior of fast electrons generated under low hybrid discharge conditions, enabling spectrum measurements at different spatial locations within the plasma. Finally, the experimental results show that the system has a good performance.

First tungsten radiation studies in DIII-D’s ITER baseline demonstration discharges

ITER Baseline Scenario plasmas were studied in DIII-D using krypton and xenon gases as a proxy for the tungsten that will be present in ITER. These impurities were chosen for having the same radiative loss rate Lz as tungsten would exhibit in the hotter ITER core. Results show that the scenario with these core radiators spans the range of impurity concentration and W radiated fraction expected for ITER, and up to 50% higher values, explored at zero injected torque, as well as 1 Nm and full co-torque injection with T ∼ 3 Nm. Stationary discharges with duration >2–4 τR are achieved with f rad ⩾ 30% leading to a reduction in confinement of ∼10%, and a comparison with real metal radiators in the same range of f rad shows that the higher Lz at the lower temperatures in these plasmas yields too pessimistic results on the survivability and performance of this scenario in ITER. Simulations of ITER power balance including W radiation show that with concentration up to three times higher than in the DIII-D plasmas the scenario can be stationary, remaining at acceptable core radiated fraction values.

The effect of emergent vegetation on flow, bedload transport, and bed morphology in a diffluence-confluence unit on a meandering channel

A diffluence-confluence unit on a meandering channel, coupled with the broadening of the divergence zone and meander circulation, promotes sediment deposition on the convex bank, forming shoals to stimulate vegetation growth, which results in water level elevation, velocity reduction, and bank stabilization. Despite these significant impacts, current research on the influence of this channel remains limited. This study conducts a series of flume experiments to quantify the influence of vegetation in a such channel on flow hydraulics, bedload transport, and bed morphology, and their inter-links. The results reveal that increased vegetation cover density subtly influences the flow depth in straight inlet reaches, triggers higher flow depth and fluctuations in the left anabranch, and induces uneven velocity distribution, especially below the crest of the curved channel. Centrifugal forces and vegetation-induced water levels shape the transverse water surface slope, resulting in a downward concave trend and unique slopes within each anabranch. The bedload transport capacity rapidly increases until an armoring layer forms, a process expedited by vegetation, particularly in high discharge conditions. This vegetation effect, amplified with higher density, enhances bedload transport rate and size but is lessened by increased discharge, which also reduces fluctuations during armoring layer formation. The statistical parameters of bed morphology at the grain-scale and structure-form-scale indicate that denser vegetation reshapes erosion dynamics across anabranches, intensifying downstream scouring and propelling the sediment deposition zone, especially under high discharge. Furthermore, the flow bifurcation ratio intensifies with escalating vegetation cover density and is assessed by a modified model consider vegetation effects with heightened precision. The apex scour depth downstream of the unit, induced by the confluence of water from both anabranches, can be characterized as a function of the dimensionless discharge and vegetation density. Concurrently, a refined model for bedload transport rate, influenced by the turbulent kinetic energy arising from emergent vegetation in this intricate reach, is proposed with high accuracy.

Vacancy formation in a 1D chain of dust particles in a DC discharge

The paper presents the first experimental observation of an atypical phenomena during self-organization of dust particles into a one-dimensional chain structure levitated vertically in the plasma of a DC glow discharge. Using a laser, the third (middle) dust particle was removed from the chain of five particles so that the positions of the remaining particles did not significantly change, and a vacancy occurred in the place of the removed particle. This state of the chain turned out to be very stable, which is confirmed by the observation of the subsequent exchange of places of the fourth and the fifth particles of the chain upon the action of the laser on the forth particle. After the exchange process, vertical positions of all particles (first, second, fourth and fifth) in the chain remained almost the same as before the exchange, and the vacancy at the position of the third particle was preserved. The experimental data and the video record of the observed phenomena as well as the estimates of the plasma parameters are presented. An assumption has been made about the mechanism of the discovered phenomena that at present discharge conditions both the vacancy formation and the dust particles positions exchange are possible due to a strong ion wakes which are formed behind the upstream dust particles of the chain.

Study on Discharge Characteristic Performance of New Energy Electric Vehicle Batteries in Teaching Experiments of Safety Simulation under Different Operating Conditions

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.

Enhancing the performance of the hybrid battery thermal management system with different fin structures at extreme discharge conditions

This study aims to enhance the performance of the air-cooled hybrid battery thermal management system (BTMS) by using fins under extreme discharge conditions such as 7C, 9C, and 11C. In this context, five different fin structures, Type-I (no fin), Type-II (rectangular), Type-III (extended), Type-IV (blade), and Type-V (triangular), were modeled, and numerical analyses of the developed BTMSs were performed using COMSOL Multiphysics software. In the numerical analysis, three different phase change materials (PCM-1, PCM-2, and PCM-3) with three different thicknesses (tPCM) of 4, 6, and 8 mm were considered, and the airflow was supplied to the system at three different Reynolds (Re) numbers of 100, 200, and 400. In this way, the effects of the BTMS types, tPCM , PCM types, and air velocity on the battery pack temperature distribution (ΔT), PCM melting uniformity (ΔF), and maximum battery cell temperature (Tmax) in the hybrid BTMS were investigated. As a result of the analyses, the maximum ΔT was found to be 5.58 °C for the case involving Type-II and PCM-1 with tPCM of 4 mm at 11C. PCM-2 exhibited the best performance for all BTMS types with a tPCM of 4 mm at 9C. However, at 11C, only the case involving PCM-3 with a tPCM of 6 mm and Type-V could maintain the Tmax under 60 °C. Moreover, the results obtained from the numerical analysis revealed that the use of fins significantly increased the PCM melting uniformity.

An evaluation of small river restoration using transient river habitat modelling for macrozoobenthos

The mandate to maintain at least a good ecological status of all surface waters has led to increased river restoration projects across Europe in the past two decades. The aim is to re-establish the hydromorphological situation and reverse the damage to freshwater ecosystems. In this study, we evaluated the restoration measures in a small stream in the State of Saxony, Germany, using the Transient River Habitat Modelling for Macrozoobenthos (TRiMM). The model was established using the Physical habitat template, covering physical habitat variables (flow, substrate, and thermal regime). It also introduces the application of a fuzzy approach to investigate river physical conditions and their effects on biological indicators like macrozoobenthos. Three taxa, namely Ancyls fluviatilis, Ephemera danica, and Gammarus fossarum, with different habitat preferences, were used to investigate the river’s ecological conditions. The model simulated the natural flow conditions from spring to summer, before and after the restoration was implemented. The research indicated that the restoration of the studied river sections succeeded in providing suitable habitats for target taxa at varied discharge conditions.

Long-term plasma exposure of ITER-like W/Cu monoblocks with pre-damaged surfaces in EAST experiments

In the ITER and future fusion devices, W/Cu monoblocks will be used as divertor target which are exposed to both steady state heat load and transient heat flux. Especially, the transient heat flux up to 10 GW m−2 during plasma disruption, is expected to induce the shallow surface damages, such as melting, and even boiling of W/Cu monoblocks. Thus, the performance of damaged W/Cu monoblocks under subsequent long-term plasma discharges is a key concern that needs to be verified and tested on existing tokamaks. Since 2022, a new type of main limiter composed of ITER-like W/Cu monoblocks has been installed and tested in EAST. The surface of W/Cu monoblocks of the limiter was damaged by the transient heat flux during the early stages of plasma construction. Subsequently, they were subjected to long-term plasma discharges over 2600 shots in normal plasma discharge conditions. This circumstance conveniently facilitates the discussion of the performance of W/Cu monoblocks with damaged surfaces especially a melting edge with hill structure under prolonged exposure to plasma. In general, the shallow damage resulting from transient heat flux on W/Cu monoblocks appears to have minimal impact on the heat exhaust capacity under steady-state heat loads, as indicated by both experimental monitoring and numerical simulation results. However, shallow melting, leading to a change in surface structure and the formation of hills, could theoretically increase local temperatures, creating potential hot spots. This phenomenon requires further validation through dedicated experiments. Moreover, the brittleness of the near-surface layer may give rise to brittle destructions, such as cracks and even dust particles, posing an additional concern. These findings yield unique qualitative conclusions that can be referenced for ITER and other fusion devices.

The dynamical response of turbulent flow to bed deformation under submerged discharge and plane vertical impinging jets

Abstract On the conditions of discharge under sluice gate and vertical jets, the research on the dynamical response of hydraulic elements to bed deformation is much concerned in the field of high-speed flow and hydraulic dredging but not be solved yet. Research achievement from numerical simulation are drawn as follows: (1) Under sluice gate discharge condition, the response of hydraulic elements to bed deformation is that the bed is deforming in the direction of the mechanical energy loss, the rate of the bed deformation and the mechanical energy loss near the local scour hole and the horizontal distance from the reattachment point to the maximum scour depth are all continuously varying with the scouring of time and synchronously approaching to its own certain value. (2) Under vertical jets discharge condition, the response of hydraulic elements to bed deformation is that the rate of bed deformation and the pressure of the maximum scour depth is monotonous continuously decreasing with the scouring of time and synchronously approaching to its own certain value.

Estuarine Adjustment: Dependence of Salinity Delay on the Forcing Timescale and Magnitude

AbstractThe salinity in estuaries continuously adapts to varying forcing for example, by discharge and tidal conditions. The changes in salinity lag behind the changes in forcing. Previous work has mostly related this delay to the adjustment time, which depends on an average background state of the estuary. Payo‐Payo et al. (2022), https://doi.org/10.1029/2021jc017523 showed that adjustment time however cannot explain the actually observed delays for a realistic salinity and forcing signal. Inspired by this, this study aims to develop relations between delay time and forcing variations and background state of the estuary. To this end, I first propose a definition of the actual delay of salinity based on wavelet analysis, applicable to observed or modeled salinity signals. To compare delay to estuarine parameters, I use a linear 1D model, but qualitative results carry over to the general case. Using model experiments with harmonic and peaked variations in the forcing, the delay time depends not only on the adjustment time, but also on the timescale of the forcing variation. Even for forcing timescales that are up to a factor 100 longer than the adjustment time, both forcing timescale and adjustment time are important for the delay. A second novel finding is that the delay depends strongly on the position along the estuary where the delay is observed. As verification, model experiments with realistically varying forcing were done, roughly inspired by the Modaomen Estuary (China). Although delay times showed a complicated and scattered dependency on model variables in this case, the above qualitative conclusions were confirmed.

A comparative study on the spectral characteristics of nanosecond pulsed discharges in atmospheric He and a He+2.3%H2O mixture

Nanosecond pulsed discharges at atmospheric pressure in a pin-to-pin electrode configuration are well reproducible in time and space, which is beneficial to the fundamentals and applications of low-temperature plasmas. In this experiment, the discharges in helium (He) and He with 2.3% water vapor (H2O) are driven by a series of 10 ns overvoltage pulses (~13 kV). Special attention is paid to the spectral characteristics obtained in the center of discharges by time-resolved optical emission spectroscopy. It is found that in helium, the emission of atomic and molecular helium during the afterglow is more intense than that in the active discharge, while in the He+2.3%H2O mixture, helium emission is only observed during the discharge pulse and the molecular helium emission disappears. In addition, the emissions of OH(A-X) and Hα present similar behavior that increases sharply during the falling edge of the voltage pulse as the electrons cool down rapidly. The gas temperature is set to remain low at 540 K by fitting the OH(A-X) band. A comparative study on the emission of radiative species (He, He2, OH and H) is performed between these two discharge cases to derive their main production mechanisms. In both cases, the dominant primary ion is He+ at the onset of discharges, but their He+ charge transfer processes are quite different. Based on these experimental data and a qualitative discussion on the discharge kinetics, with regard to the present discharge conditions, it is shown that the electron-assisted three-body recombination processes appear to be the significant sources of radiative OH and H species in high-density plasmas.

Prediction method of centrifugal pump running in turbine mode based on losses analysis

Interest of Pump as Turbine (PAT) is growing with diverse applications in engineering. Usually, the data of PATs are not available in the hands of pump manufacturers. Therefore, performance prediction methods appear as an important research area of PATs. The current prediction methods reposed on expensive, inaccurate and time consuming experimental methods. In the scope of this work, a generic and robust prediction method is built up for a centrifugal impeller PAT. The most significant hydraulic losses were derived in PAT mode, these are namely, the shock losses at the impeller inlet, the swirling losses at the impeller outlet and the impeller wall frictional losses. The Euler head, the available total head and the hydraulic efficiency were computed as well. The global efficiency was computed taking into account the machine mechanical and volumetric efficiencies, enabling therefore to perform comparison of the new prediction method with experimental, computational fluid dynamic (CFD), Rossi and Perez performances prediction methods. From where it resulted a good agreement between the given prediction methods for the entire range of operation, confirming the robustness and the applicability of the developed prediction method. The relative difference between the new prediction method and CFD data and between the new prediction method and experimental data remained higher for lower discharge conditions, notably for extreme part load conditions, where a small error could result in very high relative difference.

The urgent need to reduce phosphorus discharges for sustainable mangrove wetland management

Phosphorus affects microbial metabolic activity, nitrogen and carbon cycling in mangrove sediment, but its influence on carbon stability and greenhouse gases emission remains unclear. This study compared greenhouse gases (CO2, N2O, and CH4) emissions from mangrove sediment receiving wastewater containing various phosphorus concentrations, and evaluated its long term effect on sediment carbon flux when phosphorus pollution is eliminated. Significant increases in greenhouse gases flux and decrease of total organic carbon and readily oxidizable organic carbon in the sediment were observed after phosphorus discharge. Specifically, the N2O flux was reduced significantly at high phosphorus levels while the CO2 flux and the microbial biomass organic carbon was increased. The copy numbers of ammonia oxidation (AOA-amoA, AOB-amoA) gene, denitrification (narG, nirK) gene and methanogenesis (mcrA) gene increased with the increasing phosphorus concentration. During the wastewater discharge period for 70 days, the global warming potential of sediment flux at high phosphorus discharge condition was more than 4 times that of the control group, and the loss of total organic carbon and readily oxidizable organic carbon was 4.66 % and 7.1 %, respectively. During the remediation period (71–101 days), the greenhouse gases flux decreased rapidly, ends up with a similar level of the control group. Our results indicate that using mangrove wetland for pollution minimization in the coastal aquaculture industry could increase greenhouse gases emisison significantly, it is therefore essential to reduce phosphorus discharges from various anthropogenic activities, and local authorities must set up more stringent discharge standards in the future.

Experimental study of simple flumes with converging triangular walls

For water management, the accurate measurement of discharge in irrigation channels is essential. Static flow measuring devices such as weirs and flumes play a significant role in discharge measurement in open channels. Flumes are one of the most commonly used devices for flow measurement. Many researchers have focused on application of simple flumes in irrigation networks. This investigation aims to study the flow discharge through a simple flume with converging triangular walls under free-flow conditions. The flume is constructed by placing two right-angled triangular plates on either side of a rectangular open channel. The channel cross section is rectangular while height of the converging walls reaches to zero at the end of the flume opening. The proposed flume is inexpensive, its operation is simple, its installation is easy and does not require high maintenance (maintenance free). The present study is designed to determine the effect of different variables on flow discharge of this kind of flumes. For this, an experimental program was conducted under upstream subcritical flow regime and under free outflow conditions to formulate the flow discharge of the flume. Flume discharge relationship was deduced using dimensional analysis method and then calibrated using the experimental data collected in this study (318 runs). The proposed discharge equation has an average absolute relative error of 1.66 %, and for 96.5 % of the measured discharge values, the relative errors are within ±5 %. To reliably estimate the flume discharge, free-flow and submerged-flow conditions should be distinguished. For this, suitable equation with an average absolute relative error less than 3.44 % was presented to estimate the submergence threshold. This flume is suitable for the rectangular channel for accurate measurement of free flow at any location on field. This particular device has considerable advantages over the other devices, as it can be quickly installed and removed for use in irrigation channels. The findings and results of this study will be of interest for practical applications.

Rates of air flow in and out of closed atmospheric-pressure plasma jet system affected surface properties of treated polysulfone membrane

The cold plasma jet works in an atmospheric-pressure condition, and is used to modify polymer membranes by creating hydrophilic functional groups on the membrane surface. Since it can be used without a pressure-reducing system, treatment time and cost are reduced. However, the plasma jet has a narrow beam which limits the area of the membrane surface that can be activated. In this study, a plasma jet was generated in a closed system with controllable rates of air flow in and out of the system. The plasma discharge was recorded with a camera and analyzed by optical emission spectroscopy (OES). Polysulfone membrane surfaces were treated with various conditions of plasma discharge, and the induced membrane hydrophilicity was assessed from water contact angle (WCA) and surface energy (SE) measurements. Atomic force microscopy (AFM), Fourier Transform Infrared Spectroscopy (FTIR) and WCA contour mapping were respectively employed to study surface roughness, functional groups, and WCA distribution on the treated membrane surfaces. The airflow had distinctly different effects on the plasma characteristics. The inflow rate condition affected the width of the plasma beam, and the outflow rate condition affected the diffusion of the plasma beam. Water flux was changed according to the plasma characteristic, and an air outflow rate of 6 L/min was the optimum condition for this experiment.