深圳大学学报理工版

多级降压收集极是太赫兹行波管中回收废电子注的重要部件,对整管工作效率有重要影响.为提升整管工作效率,提出一种非轴对称结构的太赫兹频段行波管降压收集极的设计方案.通过研究注波互作用后的废电子注能量特性,设计了轴对称太赫兹频段行波管降压收集极结构,再采用非轴对称结构进行优化.三维粒子模拟计算结果显示,在考虑二次电子发射的情况下,采用三级轴对称降压收集极的太赫兹行波管,最佳回收效率为79.30%,粒子回流率为3.12%,整管工作效率为4.47%; 而当采用三级非轴对称结构降压收集极时,太赫兹行波管的回收效率升至89.50%,粒子回流率降至0.53%,整管工作效率为8.38%.采用非对称结构设计的降压收集极可有效提高太赫兹行波管的整管工作效率.

The multi-stage depressed collector(MDC)plays an important role in the terahertz traveling wave tube(TWT)for recovering spent electron beam, which has significant impact on its working total efficiency. For the purpose of improving the efficiency of the whole tube, the designscheme method of a depressed collector with non-axisymmetric structure in terahertz TWT is proposed. The axisymmetric depressed collector for terahertz TWT is designed by analyzing the energy characteristics of spent electron beam after beam-wave interaction, and then on-axisymmetric structure is used for optimization. The results of three-dimensional particle simulation(PIC)show that for the TWT with the three-stage axisymmetric MDC, the optimal recovery efficiency is 79.30%, electron reflux rate is 3.12%, and the working efficiency is 4.47% when considering the secondary electron emission. For the TWT with the three-stage non-axisymmetric MDC, the recovery efficiency increases to 89.50%, the particle reflux rate decreases to 0.53%, and the whole tube working efficiency reaches 8.38%. The working efficiency of the whole tube can be increased effectively by taking the asymmetric structure.

引言
1 废电子注能量特性分析
2 轴对称降压收集极的设计
3 非对称降压收集极的设计
4 结语

表1 PIT文件中部分废电子信息<br/>Table 1 Information of part of spent electrons in PIT

表1 PIT文件中部分废电子信息
Table 1 Information of part of spent electrons in PIT

图1 径向粒子特性<br/>Fig.1 Radial particle properties

图1 径向粒子特性
Fig.1 Radial particle properties

图2 一个射频周期内不同能量粒子分布直方图<br/>Fig.2 Histogram of particle energy distribution in one radio frequency

图2 一个射频周期内不同能量粒子分布直方图
Fig.2 Histogram of particle energy distribution in one radio frequency

图3 轴对称降压收集极结构图<br/>Fig.3 Structure diagram of symmetrical collector

图3 轴对称降压收集极结构图
Fig.3 Structure diagram of symmetrical collector

图4 三级降压收集极回收功率示意<br/>Fig.4 Recovery power of three-stage depressed collector

图4 三级降压收集极回收功率示意
Fig.4 Recovery power of three-stage depressed collector

图5 轴对称降压收集极结构示意图<br/>Fig.5 Structure diagram of symmetric depressed collector

图5 轴对称降压收集极结构示意图
Fig.5 Structure diagram of symmetric depressed collector

图6 考虑二次电子发射的轴对称降压收集极粒子轨迹<br/>Fig.6 Particle trajectory with secondary electron emission in symmetric MDC

图6 考虑二次电子发射的轴对称降压收集极粒子轨迹
Fig.6 Particle trajectory with secondary electron emission in symmetric MDC

表2 轴对称三级降压收集极粒子仿真模拟结果<br/>Table 2 Particle simulation of symmetric MDC

表2 轴对称三级降压收集极粒子仿真模拟结果
Table 2 Particle simulation of symmetric MDC

图7 轴对称降压收集极电势分布<br/>Fig.7 Potential distribution of symmetrical MDC

图7 轴对称降压收集极电势分布
Fig.7 Potential distribution of symmetrical MDC

图8 非轴对称降压收集极结构示意<br/>Fig.8 Structural diagram of asymmetric MDC

图8 非轴对称降压收集极结构示意
Fig.8 Structural diagram of asymmetric MDC

表3 不同级间距离下相应指标<br/>Table 3 Results among different margins

表3 不同级间距离下相应指标
Table 3 Results among different margins

图9 考虑二次电子发射的非对称降压收集极电子轨迹图<br/>Fig.9 Electron trajectory considering secondary electron emission in asymmetric MDC

图9 考虑二次电子发射的非对称降压收集极电子轨迹图
Fig.9 Electron trajectory considering secondary electron emission in asymmetric MDC

表4 非轴对称三级降压收集极粒子模拟结果<br/>Table 4 Particle simulation of asymmetric three-stage depressed collector

表4 非轴对称三级降压收集极粒子模拟结果
Table 4 Particle simulation of asymmetric three-stage depressed collector

图10 非对称性降压收集极电势分布图<br/>Fig.10 Potential distribution of asymmetrical MDC

图10 非对称性降压收集极电势分布图
Fig.10 Potential distribution of asymmetrical MDC

图11 ANSYS稳态热分析温度分布图<br/>Fig.11 Temperature distribution of MDC in ANSYS

图11 ANSYS稳态热分析温度分布图
Fig.11 Temperature distribution of MDC in ANSYS

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备注

引言

1 废电子注能量特性分析

2 轴对称降压收集极的设计

3 非对称降压收集极的设计

4 结语

期刊信息

备注

引言

1 废电子注能量特性分析

2 轴对称降压收集极的设计

3 非对称降压收集极的设计

4 结 语

期刊信息

4 结语