高级检索

STCF对撞环弧区标准单元段布泵方案研究

Pumping Scheme for Arc Region Standard Cell of STCF Collider Rings

  • 摘要: 针对超级陶粲装置(STCF)对撞环弧区标准单元段在小周长、小孔径、高能量、高流强和高气载等极端条件下对超高真空(静态平均真空度≤5×10−9 Pa,动态平均真空度≤5×10−8 Pa)的严苛需求,本文基于试验粒子蒙特卡洛方法,采用COMSOL Multiphysics软件中的分子流模块开展了不同布泵方案下的压力分布仿真分析。研究了增大泵的抽速、采取内壁面镀膜、设置吸气剂条等措施下对弧区标准单元段静态真空度和动态真空度的影响,仿真计算结果表明:采用集中式抽气方案,由于泵口接管流导的限制,平均真空度未能达到设计指标;引入束流管内壁面镀吸气剂膜,静态平均真空度4.17×10−9 Pa,但动态还未达到设计指标;在侧室设置吸气剂条,动态平均真空度6.09×10−8 Pa,接近设计指标;在集中抽气位置增加吸气剂泵,结合前面采取的所有措施,动态平均真空度达到了4.33×10−8 Pa,满足设计指标。通过以上研究,提出了一种“集中+分布式”的抽气方案,为STCF对撞环弧区标准单元段的真空系统设计提供了设计依据和理论支撑。

     

    Abstract: For the arc region standard cell of the STCF collider rings, under extreme conditions such as small circumference, small aperture, high energy, high beam intensity, and high gas load, the demanding requirements for ultra-high vacuum (static average vacuum degree ≤5×10−9 Pa, dynamic average vacuum degree ≤5×10−8 Pa) are addressed. In this paper, based on the test particle Monte Carlo method, the molecular flow module in COMSOL Multiphysics software is used to carry out pressure distribution simulations under different pump layout schemes. The effects of measures such as increasing pumping speed, coating the inner wall surface, and installing getter strips on the static and dynamic vacuum degrees in the arc region standard cell are studied. The simulation results show that: with a centralized pumping scheme, due to the flow conductance limitation of the pump port connection tube, the average vacuum degree fails to meet the design goal; by coating the inner wall of the beam pipe with a getter film, the static average vacuum degree reaches 4.17×10−9 Pa, but the dynamic vacuum degree still does not meet the design goal; By installing getter strips in the antechamber, the dynamic average vacuum degree reaches 6.09×10−8 Pa, approaching the design goal; By adding getter pumps at the centralized pumping locations, combined with all the aforementioned measures, the dynamic average vacuum degree reaches 4.33×10−8 Pa, meeting the design goal. Through the above research, a "centralized + distributed" pumping scheme is proposed, providing a design basis and theoretical support for the vacuum system design of the STCF collider rings arc region standard cell.

     

/

返回文章
返回