Diffuse and spark discharges are formed and studied during breakdowns with nonuniform electric field in nitrogen,air,and argon at elevated pressures and pulse repetition frequency of 400 Hz.Negative-polarity voltage p...Diffuse and spark discharges are formed and studied during breakdowns with nonuniform electric field in nitrogen,air,and argon at elevated pressures and pulse repetition frequency of 400 Hz.Negative-polarity voltage pulses of the amplitude 20 kV,width at the base of 15 ns and rise time of 2 ns are applied to the electrode with a small radius of curvature.In the conditions of generation of runaway electron beams and X-rays,a CCD camera records the time of the diffuse discharge formation and its duration prior to its transition to a spark one.In all three gases,the diffuse discharge is formed during the time not exceeding 1 ns,when the bright spots appear on cathode in argon and air resulting in the beginning of the spark channel propagation.展开更多
The paper reviews the results of investigations of the low-current atmospheric-pressure discharges in gas flow.The attention is focused on the discharges in electrode systems of coaxial plasmatron and of so-called gli...The paper reviews the results of investigations of the low-current atmospheric-pressure discharges in gas flow.The attention is focused on the discharges in electrode systems of coaxial plasmatron and of so-called gliding arc.It is demonstrated that a considerable fraction of discharge current is carried by a plasma column operating in a regime of normal glow discharge with occasional transitions to spark.The nature of glow-to-spark transition is discussed.Beside the plasma column,a weakly ionized gas fills in the interelectrode gap and forms a plasma jet at the exit of electrode system.The jet contains the active chemical particles that play important role in different discharge applications.The applications in plasma assisted combustion systems,for surface treatment with a usage of plasma jet,and for biology and medicine are considered.展开更多
快速高效地识别局部放电类型不仅对电力设备的状况评估具有十分重大的意义,而且能够实现智能电网下对电力设施监测数据的快速诊断。因此,在Spark计算框架的基础上提出基于VPMCD(Variable Predictive Model Based Class Discriminate)的...快速高效地识别局部放电类型不仅对电力设备的状况评估具有十分重大的意义,而且能够实现智能电网下对电力设施监测数据的快速诊断。因此,在Spark计算框架的基础上提出基于VPMCD(Variable Predictive Model Based Class Discriminate)的局部放电模式识别的并行化方法。采取对原始放电信号提取其φ-q-n图谱的PRPD(Phase Resolved Partial Discharge)特征构成相关特征向量作为实验输入,采取并行化VPMCD算法对放电类型进行分类。实验结果和分析表明,在Spark计算框架下的分布式处理的计算效率要优于传统单机环境下的计算效率,加速比随着节点数和数据量的增多而显著提升,可以满足智能电网下大数据快速处理的要求。展开更多
基金Project supported by Russian Foundation for Basic Research(under Grant12-08-00105_a)
文摘Diffuse and spark discharges are formed and studied during breakdowns with nonuniform electric field in nitrogen,air,and argon at elevated pressures and pulse repetition frequency of 400 Hz.Negative-polarity voltage pulses of the amplitude 20 kV,width at the base of 15 ns and rise time of 2 ns are applied to the electrode with a small radius of curvature.In the conditions of generation of runaway electron beams and X-rays,a CCD camera records the time of the diffuse discharge formation and its duration prior to its transition to a spark one.In all three gases,the diffuse discharge is formed during the time not exceeding 1 ns,when the bright spots appear on cathode in argon and air resulting in the beginning of the spark channel propagation.
基金Project supported by Russian Foundation for Basic Research(under Grants 11-08-00671,13-08-98110)
文摘The paper reviews the results of investigations of the low-current atmospheric-pressure discharges in gas flow.The attention is focused on the discharges in electrode systems of coaxial plasmatron and of so-called gliding arc.It is demonstrated that a considerable fraction of discharge current is carried by a plasma column operating in a regime of normal glow discharge with occasional transitions to spark.The nature of glow-to-spark transition is discussed.Beside the plasma column,a weakly ionized gas fills in the interelectrode gap and forms a plasma jet at the exit of electrode system.The jet contains the active chemical particles that play important role in different discharge applications.The applications in plasma assisted combustion systems,for surface treatment with a usage of plasma jet,and for biology and medicine are considered.
文摘快速高效地识别局部放电类型不仅对电力设备的状况评估具有十分重大的意义,而且能够实现智能电网下对电力设施监测数据的快速诊断。因此,在Spark计算框架的基础上提出基于VPMCD(Variable Predictive Model Based Class Discriminate)的局部放电模式识别的并行化方法。采取对原始放电信号提取其φ-q-n图谱的PRPD(Phase Resolved Partial Discharge)特征构成相关特征向量作为实验输入,采取并行化VPMCD算法对放电类型进行分类。实验结果和分析表明,在Spark计算框架下的分布式处理的计算效率要优于传统单机环境下的计算效率,加速比随着节点数和数据量的增多而显著提升,可以满足智能电网下大数据快速处理的要求。
