The anode and the cathode of the cylindrical Π\Pi cathode diode are not coaxial, and the quantitative calculation of its space charge limited current (SCLC) has not been reported. In this article, we propose the SCLC quantitative expression of cylindrical Π\Pi cathode diode through improving the theory model of Japanese distinguished scholar Y. Koike ( ) based on the 3/2 power law of SCLC of the coaxial cylindrical diode and study the relationship between current and cathode structure of cylindrical Π\Pi cathode diode by using the numerical simulation method based on the CST Particle Studio (CST-PS). This improved model is more suitable than previous empirical formulas when the radius of a single cathode is greater than or equal to 1.0 mm and can be used in combination with the theory model of Y. Koike to estimate quantitatively the SCLC of cylindrical Π\Pi cathode diode. Moreover, it also provides an effective basis for the design and optimization of the Π\Pi cathode structure of the high-power vacuum transmitting tube.

中文翻译：

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圆柱形二极管的螤阴极结构与阴极电流定量关系的研究


圆柱形π\Pi阴极二极管的阳极和阴极不同轴，其空间电荷极限电流(SCLC)的定量计算尚未见报道。本文在同轴圆柱二极管SCLC的3/2幂律的基础上，通过改进日本著名学者Y.Koike( )的理论模型，提出了圆柱Π\Pi阴极二极管的SCLC定量表达式，并研究了其关系采用基于CST Particle Studio（CST-PS）的数值模拟方法，对圆柱形Π\Pi阴极二极管的电流与阴极结构进行了比较。当单个阴极半径大于或等于1.0 mm时，该改进模型比以往的经验公式更适用，并且可以与Y. Koike的理论模型结合使用来定量估计圆柱形Π\Pi阴极的SCLC二极管。同时也为大功率真空发射管π\Pi阴极结构的设计和优化提供了有效的依据。