Thermal analysis of Faraday cup analyzer for measuring electron beams of traveling wave tubes(TWTs) using ANSYS package is presented. With beams of different power density and different pulses, temperature of the Faraday cup had been simulated. The results show that with a single pulse, only temperature of spot size on aperture plate rises quickly, whereas temperature of other part is constant. For normal operating, pulse width must be smaller than 0. 5 μs, 0. 1 μs and 0, 2 μs are better, to measure beams of power density larger than 5× 106 W/cm2. Pulse width for measuring a beam of fixed power density should be limited, and different pulses should be used for measuring different power density beams. In addition, taking heat cumulating effect into account, suitable pulse repetition frequency should be set for Faraday cup working at appropriate temperature. The results show that 10 Hz to 100 Hz is suitable.%利用ANSYS软件对测量行波管电子注截面的法拉第筒探头进行了热分析研究.分析了在单脉冲情况下,测量各种直径的不同脉冲功率密度的电子注、不同脉冲宽度对法拉第筒温度的影响,研究了测量不同功率密度的电子注可以使用的脉冲宽度.结果表明,仅法拉第筒上的注斑区域温度迅速上升,温度梯度较大,其它部分温度基本不变,为保证法拉第筒能够持续正常工作,在单脉冲情况下,对于功率密度大于5×106W/cm2的电子注,需使用宽度小于0.5 μs的脉冲,最好是0.1μs和0.2μs的脉冲进行测量,与文献结果相符.测量一定功率密度的电子注,需选择合适的脉冲宽度.另外,考虑热量的累积效应,分析了脉冲重复频率对法拉第筒工作温度和散热情况的影响.结果表明,脉冲重复频率设为10～100 Hz是比较合适的.
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