访欧报告

1. 访欧报告 第21届SOFT 第4届CHATS WORKSHOP on SECRETS IPP,KFZ,CRPP

2. 日程 • Sep. 6-8 第4届CHARTS, Frascati • Sep. 11-15 第２１届SOFT, Madrid • Sep. 18-22 访问IPP, FZK, Germany • Sep. 25 访问CRPP, Switsland • Sep. 26-28 Workshop on SEGARETS

3. 第21届ＳＯＦＴ • 会议概况 • 欧洲的核聚变研究情况 • 欧洲的核聚变技术研究计划 • 关于ＩＴＥＲ

4. 会议概况 • 500多人参加 • 19篇邀请报告 • 23篇口头报告 • 375篇书面报告 • 主要领域：偏滤器和第一壁；加热；控制；磁体，超导及电源；粒子循环；装置设计，装置技术；包层；环境，辐射与安全；诊断；遥控操作；慣性约束。

5. 欧洲的核聚变研究情况 Policy and Perspectives of European Fusion ResearchU.Finzi, Director,Energy and Environment Research Directorate General, European Commission . All the fusion research in EU is directed towards a single, long-term objective:”the joint creation of prototype reactors for power stations to meet the needs of society: operational safety,environmental compatibility,economic viability”

6. Next step of 5th Framework program: JET & industry to develop the capacity to construct an experiment reactor & prepare to operate it; Concept improvement (structured activity in the field of physics to improve the basic concept of fusion device); Long-term technology (structured technological activities which are essential to make progress with harnessing fusion, plus safety and environment study).

7. Organisation European Fusion Development Agreement (EFDA) has been established Its scope includes: Technology activities; The collective use of the JET facilities; The EU contributions to International collaboration such as ITER.

8. 欧洲的核聚变技术研究计划(1) TWO main lines • R&D for the Next Step, at present ITER Solving the technological & Engineering problems encountered in the design and construction: in particular the use of tritium, the behaviour of PFC reliability, maintenance problem and improvement and benchmarking of safety code.

9. 欧洲的核聚变技术研究计划(2) • Long Term development of neutron resistant, low activation materials, design and R&D of possible tritium breeding blanket concepts and finally on the study of 14 MeV neutron source for fusion releavant materials. Safety, Environment, and economic aspects of Fusion.

10. 关于ＩＴＥＲ(1) • The world program is scientifically & technically ready to take the important ITER step. • The design of ITER approaching the 50% cost saving target, still satisfies the overall objective of ITER. • The lower costs of the new design allows whilst maintaining a good balance in the domestic program of each party.

11. 关于ＩＴＥＲ(2) • The key tasks for the fusion community are now to confirm the strategic priority to proceed with ITER in an International collaboration as a centrepiece of the world fusion energy development program, to determine, with other potential participants, the overall terms of an international frame for joint construction and operation, and prepare of the programme organization.

12. ＣＨＡＲＴＳ • 4th Workshop on Computation of tHermo-hydrAulic Transients in Superconductors • 参加人数：32 • 参加单位：15 • 邀请报告：2 • 口头报告：21 • HT-7U导体设计受到重视。

13. 内容简介 • 超导导体，线圈实验结果及其分析计算。（ITER CSMC，SeCRETS,W7-X，LHC) • 超导导体失超模拟，及其他有关热工，水力，电分析计算模型。 • 超导导体中电流分布的有关实验和分析计算模型。 • HT-7U TF and PFConductor design

14. 和我们有关的几个问题 • 在ITER CSMC 和W7-X实验中发现导体有性能退化。 • 在QUELL实验中探索了失超检测的几种方法。 • 在SEGRETS实验中发现一些新现象。 • 应对电流分布问题予以重视。 • 我们需要加强超导模拟计算。

15. SECRETS • 参加人员：27人 • 单位：CRPP，ITER JCT, ENEA Frascati, U. Twente, LLNL, CEA Cadarache, FZK Karlsruhe, EFDA Garching, Kurchatov Inst.,VNIINM, VNIKP, ASIPP. • 议题：对“SECRETS”实验做评估。

16. 实验目的 • 调查在相应运行条件下承受模拟ITER等离子体破裂时横向场瞬间变化所必需的最小温度裕度。 • 通过直接比较，调查在相应运行条件下，外加铜线在Nb3Sn CICC中对瞬态稳定性的贡献有多大。

17. 实验项目 • DC measurement ( Ic vs. B&T,Tcs vs. B&I) • calorimetric ac losses vs. B & Iop • transient stability as a function of temperature margin, mass flow rate, operating current density & transient duration (32 ms and 65 ms) • stability for simulated plasma disruption transient as a function of temperature margin. • Current distribution measurement during dc and transient operation.

22. 实验结果 • DC 临界电流和分流温度的比较。 • 交流损耗 • 等离子体破裂 • 瞬态稳定性和温度裕度的关系 • 瞬态稳定性和扰动周期的关系 • 瞬态稳定性和运行电流的关系 • 瞬态稳定性和氦质量流量的关系 • 电流分布

35. 值得注意的几个结果 • 在很小的温度裕度下极高的瞬态稳定性（高于氦的焓值，无法解释） • 外加铜线导体具有较高的横向电阻，较低的交流损耗，较高的分流温度和临界电流。但是具有较低的瞬态稳定性。即外加铜线对稳定性的贡献不大(poor effect) • 流量对稳定性的影响很大。 • 没有观察到从良好冷却区到病态冷却区的过渡。

36. 问题，评论和建议1 • n值由导线的30降到导体的15的原因不可能是由于自场效应。The possible reason for the “n”value observed in the cable(15 compared to =30 in the strand), PB explained by the self field much larger in cable, NM disagree. • 接触电阻比CSMC 高。(the results on Secrets show the coupling loss time constants, nτ, in the range of 1-2 ms. Measurements at T. U. in the virgin state show about 15ms. The average inter strand resistance measured at U.T of sub-cable of CS1(29nΩ· m) and CS2(109nΩ· m) was lower than Secrets (220 and 450nΩ· m). After cycling, the deduced one would be 1-2 μΩ · m, i.e in the range between CS1 and CS2. • 对交流损耗的结果有疑问：管壁涡流是否会造成屏蔽效应；频率不够低。 • 等离子体破裂模拟中磁场的幅值不够, low frequency proably more severe and have not simulated。The field applied in plasma disruption is an open field pulse.

37. 问题，评论和建议2 • 稳定性实验的结果中能量的沉积是否准确？关于极限电流的讨论: JLD noted that there was no verification of the actual enegy going into the conductor in the stability pulses. The only logical conclusion about the ‘stability margin is great than the available helium enthalpy is that the deposited energy is even smaller than predicted from the 2ms coupling loss. The conventional inflexion point which isexpected at Iop=Ilim is not observed. DB presented Gandalf simulatons of the Secrets conductor, which suggest a transition at about I/Ic of about 0.5. The Secrets experiment shows an unexpected results that there is no such limiting current, unless it is in the region of I/Ic>0.9-0.95. NM, the use of the ‘limiting current’ design criteria to try locate this transition is invalid, he said he is not arguing against the existence of Ilim, only that you should not use anempirically based design tool for post test analysis. • 应进一步做实验，并用Gandalf 对所有实验进行模拟。

38. HT-7U导体设计的建议 • Segregated 铜线在HT-7U中是可用的。 • 建议用镀Ni代替镀Cr以减小横向电阻，改善电流的再分布。 • 空隙率应严加控制，保持在34%-35%。 • 子缆的花包将影响电流的再分布和氦的径向流动，建议取消。(michel, Bruzzone) • 电流的再分布主要发生在子缆内，建议如用镀Ni，子缆可花包。如镀Cr，则不包。（Sytnikov)

39. 其它有关技术（1） • ASDEX-U的门：一维运动。 • 真空：烘烤温度： 建议用150度，不会引起电磁测量等元件的麻烦。冷，热壁运行：从ASDEX-U十年的运行情况，看不到热壁运行的需求。分子泵的位置：尽可能靠近（采用屏蔽铁块）。偏滤器抽气：注意饱和及返流，KSTAR 低温泵饱和时间100秒在再生或被加热时会有高气压。直接接计算机的真空计；为保证安全每个系统有两套计算机控制。

42. 其它有关技术（2） • 电阻位移监测计和集成电路罗科线圈。 • Toska 装置：窗口，底部支撑，线圈固定。 • ITER TFMC 的失超探测方法。 • ITER TFMC 的接头。 • TFMC 工艺流程：线圈绕制-热处理-包匝间绝缘-包饼间绝缘-VPI-接头制作-包对地绝缘-入盒-焊盖充沙-VPI。