电工技术学报2025,Vol.40Issue(21):6806-6818,13.DOI:10.19595/j.cnki.1000-6753.tces.250140
纳秒脉冲激励下氩掺乙醇冷等离子体射流的放电特性
Discharge Characteristics of Ar+EtOH Cold Plasma Jet under Nanosecond Pulse Excitation
摘要
Abstract
Atmospheric pressure cold plasma jet does not require vacuum equipment,is small in size,low in cost and easy and safe to operate.It can generate a variety of active species to react physicochemically and chemically with the surface of the treated material,and has been widely used in the fields of materials science,biomedicine and environmental engineering.Although He plasma jet has excellent performance but is expensive,and the alternative Ar plasma is easy to form unstable filamentary discharge,and the discharge temperature is high with the risk of burns.Scholars at home and abroad have proposed a variety of ways to realize the diffuse discharge of Ar plasma at atmospheric pressure,such as the use of pulsed power supply,reducing the air gap between the electrodes and doping a small amount of easily ionizable gases.In this paper,a small amount of ionizable gas ethanol is doped into Ar to transform the Ar plasma jet into a stable,dispersive plasma jet with low breakdown voltage and close to room temperature,and the effects of different parameters of the driving power supply,the size of the ethanol doping concentration,and the external environment on the discharge characteristics of the Ar+EtOH plasma jet are investigated under nanosecond pulse excitation. Firstly,two plasma jet source structures-with and without quartz shielding-were designed.Secondly,the Ar+EtOH atmospheric pressure cold plasma jet discharge and detection platform are built.Finally,the effects of different discharge parameters and ethanol doping concentration on the characteristics of Ar+EtOH plasma jets were systematically investigated by discharge image analysis,voltage-current characterization,and emission spectral analysis. The plasma diagnosis revealed that the diffusion discharge could not be realized with either too high(>0.99%)or too low(<0.02%)ethanol doping concentration,and the lower limit of the ethanol doping concentration gradually increased from 0.02%to 0.08%with the increase of the applied voltage from 4 kV to 9 kV,whereas the upper limit of the ethanol doping concentration firstly increased to 0.99%at 6 kV,and then decreased to 0.73%.the dispersive discharge interval was expanded after shielding from ambient air effects.The increase in both voltage and frequency enhanced the discharge intensity of the plasma jet.As the voltage was increased from 4 kV to 9 kV,the discharge current amplitude was increased from 20 mA to 311 mA,the current onset time was increased from 340 ns to 102 ns,and the intensity of the Ar*(763 nm)emission line was increased from 0.087×104(au)to 5.66×104(au).When the frequency was increased from 1 kHz to 25 kHz,and the current amplitude was kept at about 108 mA,the current onset time was increased from 292 ns increased to 88 ns,and the Ar* emission intensity increased from 0.27×104(au)to 5.64×104(au).Low ethanol doping concentration(0.06%~0.28%)increased the discharge current amplitude from 85 mA to 116 mA and advanced the onset time from 240 ns to 108 ns,which may be due to Penning ionization between the ethanol molecule and the substable Ar*.However,excess ethanol doping significantly reduced the OH and Ar* concentrations,suggesting that the ethanol molecules consumed the substable Ar*. The following conclusions can be drawn from the experimental analysis:(1)The appropriate ethanol doping concentration is the key to realize the dispersive discharge of the argon plasma jet,and its optimal range is related to the applied voltage.(2)Shielding the ambient air increases the diffuse discharge interval by eliminating the electronegative oxygen effect.(3)Increases in both voltage and frequency increase the discharge intensity of the Ar+EtOH plasma jet,but frequency does not affect the amplitude of the discharge current,only the onset moment of the discharge current.(4)Low ethanol doping promotes plasma discharge through Penning ionization,while overdoping depletes the active component and reduces the discharge intensity of the jet.关键词
纳秒脉冲/冷等离子体射流/氩气/乙醇/放电特性/发射光谱Key words
Nanosecond pulse/cold plasma jet/argon/ethanol/discharge characteristics/emission spectra分类
信息技术与安全科学引用本文复制引用
夏文杰,吴锦昕,何彬,郭自凯,王治远..纳秒脉冲激励下氩掺乙醇冷等离子体射流的放电特性[J].电工技术学报,2025,40(21):6806-6818,13.基金项目
国家自然科学基金(52107237)和河北省省级科技计划(24464401D)资助项目. (52107237)