基于蒙特卡罗方法的HL-3装置中性束中性化送气优化研究  

Optimal Study on Neutralizer Gas Supply Base on Monte Carlo Method for HL-3 Neutral Beam Injection

作　　者：杨宪福 余珮炫 周博文 周红霞 YANG Xianfu;YU Peixuan;ZHOU Bowen;ZHOU Hongxia(Southwestern Institute of Physics,Chengdu 610200,China)

机构地区：[1]核工业西南物理研究院,成都610200

出　　处：《真空与低温》2025年第2期165-170,共6页Vacuum and Cryogenics

基　　金：自然科学基金青年基金(11605045)。

摘　　要：在磁约束聚变中性束加热系统的中性化器中,足够的气体靶才能使离子束实现最佳中性化效率,同时这些气体作为注入器真空室的气体负载,希望越少越好。为了优化最佳气体靶厚所需的气体流量,根据中性化器中气体流态特性,采用基于试验粒子蒙特卡洛方法的模拟程序对中性化器气体分子分布进行模拟,该模拟程序研究分子与器壁碰撞反应的发射角度和飞行速度两个变量对分子密度的影响,得到中性化送气的优化方案。研究结果表明,中性化送气角度会影响气体靶厚,送气角度与束流夹角150°为最优;中性化器壁温度也会影响气体靶厚,相同气体流量在更低的温度下能得到更大的气体靶厚;气体温度还会导致建立最佳气体靶厚的时间发生变化,温度越低,耗费的时间则越长。研究结果为中性化器结构的优化设计和实验控制提供了理论依据和数据支撑。In the neutralizer of the magnetic confinement fusion neutral beam heating system,the gas target is the medium for the ion beam to be converted to a neutral state,and sufficient gas target thickness can make the ion beam achieve the optimal neutralization efficiency.However,this gas is used as gas load in the vacuum chamber,and it is hoped that the less the better.In order to optimize the flow required for the optimal target thickness,it is expected to obtain the optimal target thickness with less gas flow.According to the molecular flow characteristics of the gas in the neutralizer,a code based on the test particle Monte Carlo method was used to simulate the distribution of the molecules in the neutralizer.In this code,the emission angle and flight velocity of molecules in the collision reaction were taken as the objects to study the molecular density,and the integral of molecular density in the length direction of the neutralizer reflected the size of the target thickness,so as to obtain the optimization scheme.The results show that the emission angle of the molecule after collision is random,but the neutralizer gas supply angle can affect the target thickness.The angle between the direction of the gas supply and the direction of the beam is the best at 150°,the worst at 15°,and it is consistent with the law of the average number of collisions of molecules in the neutralizer.After each collision,the molecule gets the temperature of the wall,which makes its flight velocity change,so the neutralizer wall temperature will also affect the target thickness.The same flow can obtain a larger target thickness at a lower temperature.In particular,when the temperature is below 100 K,the influence of temperature on the target thickness is more obvious,and the slope of linear fitting is 5 times that of higher than 100 K.The temperature also causes a change in the time to establish the optimal target thickness,and the lower the temperature,the longer the time.The results provide theoretical basis and data support for the

关 键 词：中性束 中性化效率 蒙特卡洛方法 气体靶厚 

分 类 号：TB69[一般工业技术—制冷工程] TL62[核科学技术—核技术及应用]