星载行波管高效率、高可靠阴极热子组件研究

Simulation of Thermal and Mechanical Behavior of Cathode-Heater Assembly of Spaceborne Traveling Wave Tube

阴极热子组件是星载行波管的核心部件,其性能的好坏直接影响到整管的性能和寿命。由于星载行波管工作环境特殊,要求在保证阴极正常工作的前提下,尽可能地降低阴极热子组件的加热功率以提高阴极热子组件可靠性、延长阴极热子组件寿命,同时阴极热子组件必须具有良好的抗振性能。本文利用ANSYS有限元软件对某星载脉冲行波管栅控电子枪阴极热子组件进行了热学和结构动力学性能分析和研究,通过优化阴极热子组件支撑结构和尺寸,降低了它的加热功率,并进行了热学实验验证;同时为了保证其力学可靠性,分析了阴极热子组件在随机振动条件下的力学性能。研究结果表明,新阴极热子组件结构加热功率由10.50 W降低至8.21 W,轴向尺寸缩短了45.4%,满足某星载行波管小型化的需求,结构同时符合抗机械振动性能的要求。

The thermal property andvibrational behavior of the cathode-heater assembly with grid-controlled pulsed electron gun, installed in space-borne traveling wave tube, was empirically approximated, mathematically modeled, theoret- ically analyzed, numerically simulated in finite element method with software ASYST, and experimentally measured to in- crease its efficiency and reliability in space flight environment. The impact of the heat transport modes, including the heat conduction,heat convection and heat radiation, on the heating efficiency was investigated and the vibration resistance of the cathode-heater assembly with the optimized supporting structure was evaluated. The calculated and test results show that optimization of the cathode-heater assembly reduced its heating power from 10.50 to 8.21 W and shortened its axial size by 45.4%, satisfying the requirements on miniaturization and vibration-resistance and significantly improving its effi- ciency, its reliability and its service-life.