中性束注入器低温真空系统运行参数调节研究

Adjustment of operating parameters of cryo-vacuum system for neutral beam injector

采用大抽速低温泵作为中性束注入器(Neutral Beam Injector,NBI)真空系统的主抽泵已成为当前NBI发展的趋势,为确保NBI低温真空系统的真空性能满足运行要求,需研究其运行参数调节的依据与措施。根据全超导托卡马克核聚变实验装置(Experimental Advanced Superconducting Tokamak,EAST)的NBI对真空性能的要求,确定了液氮、液氦管路出口合适的运行温度和压强范围。分析液氮和液氦管路出口压强改变的原因,设计出维持该运行条件而必须采取的调节措施,得出了压强改变原因判断及解决流程图,并利用该流程图进行了实验验证。结果表明,对液氮管道出口压强和温度改变的原因分析正确,设计相应的解决流程合理可行。

It has become the trend to adopt the cryopump with high pumping speed as the main pump of the vacuum system for neutral beam injector(NBI).In order to ensure that the vacuum performance of NBI cryo-vacuum system can meet the operating requirements,it is necessary to study the basis and measures of adjusting the operating parameters.According to the requirements of vacuum performance of Experimental Advanced Superconducting Tokamak(EAST)NBI,the suitable operating temperature and pressure range at the outlet of liquid nitrogen and liquid helium pipeline were determined.The reasons for the change of outlet pressure of liquid nitrogen and liquid helium pipeline were analyzed,and the adjustment measures that must be taken to maintain the operating conditions were designed,and the flow chart of the judgment and solution of pressure change reasons was obtained,which was verified by experiments.The results show that the reasons for the change of pressure and temperature at the outlet of liquid nitrogen pipeline are analyzed correctly,and the corresponding design process is reasonable and feasible.