新型热阴极电子枪加热结构热分析

Thermal analysis of heating structure for thermionic cathode electron gun

利用ANSYS和COMSOL仿真模拟软件,对热阴极电子枪的加热结构进行热分析,得到了阴极加热结构设计的一些规律,然后通过实验对一系列加热结构进行阴极温度测试,进一步验证模拟计算的结果,得到了一种加热效率比较高的结构。该结构在加热功率为100 W时,阴极温度超过了1 900 K,达到了铱铈阴极的工作温度。在阴极温度1 800 K左右,阴极表面引出电场强度为3.6×106V/m的条件下,该阴极的最大发射电流达到1.04 A,发射电流密度约13 A/cm2。

Some thermal analysis results of several heating structures for thermionie cathode electron gun by using ANSYS code and COMSOL code were presented in this paper, and some instructions for heating structure design were obtained. A series of heating structures of thermionic cathode were tested in experiments, verifying the results of the thermal analysis, and so an ef- ficiency heating structure was attained. In this structure, at a heating power about 100 W, the temperature of cathode was more than 1 900 K which meets at the working temperature required by Ir Ce cathode. Under a temperature of 1 800 K and the electric field on the cathode surface of 3.6X 106 V/m, the Ir Ce cathode gives a maximum emission current of 1.04 A and the emission current density of 13 A/cm^2.