Scholarlink

<p>Cathode region of electrical arcs with volatile cathode materials and low heat conductivity was studied using kinetic model of cathode vaporization and plasma generation. This study demonstrates that in comparison with well-studied cathode materials such as copper, electrical arcs based on low melting, volatile cathode materials are unique in terms of calculated cathode and plasma parameters. The cathode plasma is characterized by low cathode potential drop, low degree of vapor ionization and plasma electron temperature in comparison to previous analysis of that data for widely studied cathodes of intermediate thermophysical properties like copper,&#xa0;silver and similar materialls. A larger ratio of heavy particle density at external boundary of the non-equilibrium (Knudsen) layer to the density of saturated vapor at the cathode temperature was found for such materials in comparison to that for Cu cathode and for target evaporation into vacuum by laser irradiation. Fundamentally, the plasma flow is strongly impeded. Therefore, the plasma velocity at the Knudsen boundary is significantly lower than the sound velocity. The rate of cathode evaporation into near cathode plasma is significantly lower than evaporation rate into vacuum caused by metal-laser interaction. Using considered cathodes in the space propulsions show important result that a high mass flow rate (comparing to intermediate materials properties) be achieved at relatively low power. This result explains the obtained high thrust, performance and thrust to power ratio for a such&#xa0;vacuum arc thruster.&#xa0;</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Features of electrical arcs with volatile and low melting cathode materials. Applications for plasma propulsion

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年7月10日

查看全文
  • Isak I. Beilis

摘要

Cathode region of electrical arcs with volatile cathode materials and low heat conductivity was studied using kinetic model of cathode vaporization and plasma generation. This study demonstrates that in comparison with well-studied cathode materials such as copper, electrical arcs based on low melting, volatile cathode materials are unique in terms of calculated cathode and plasma parameters. The cathode plasma is characterized by low cathode potential drop, low degree of vapor ionization and plasma electron temperature in comparison to previous analysis of that data for widely studied cathodes of intermediate thermophysical properties like copper, silver and similar materialls. A larger ratio of heavy particle density at external boundary of the non-equilibrium (Knudsen) layer to the density of saturated vapor at the cathode temperature was found for such materials in comparison to that for Cu cathode and for target evaporation into vacuum by laser irradiation. Fundamentally, the plasma flow is strongly impeded. Therefore, the plasma velocity at the Knudsen boundary is significantly lower than the sound velocity. The rate of cathode evaporation into near cathode plasma is significantly lower than evaporation rate into vacuum caused by metal-laser interaction. Using considered cathodes in the space propulsions show important result that a high mass flow rate (comparing to intermediate materials properties) be achieved at relatively low power. This result explains the obtained high thrust, performance and thrust to power ratio for a such vacuum arc thruster.