EAST低温系统又一新降温模式

EAST氦低温系统是EAST(Experimental Advanced Super-conducting Tokamak)先进超导托卡马克实验装置重要子系统之一;到目前为止,EAST已经成功进行了6次降温实验。第四次降温实验于2008年8月完成,这次降温实验与前几次降温实验很不相同。前3次的降温实验冷却磁体依赖四台透平膨胀机(透平A、B、C和D),透平B、C和D获得LHe去冷却PF和TF磁体、5&8对电流引线和busline到相应的温度。透平A用于制取80K的冷量冷却外冷屏。而此次降温是采用3台透平膨胀机(透平A、B和C),透平B和C与节流阀获得LHe去冷却PF和TF磁体、5&8对电流引线和busline到相应的温度。透平A还是用于制取80K的冷量冷却外冷屏。此次整个降温过程大概用了20天,比以前多耗时25%;文中给出了透平的启动过程、磁体冷却过程和一些操作经验。

Another new cooldown mode of EAST cryogenic system

The cryogenic system is an important subsystem of EAST tokamak, which has been cooled down for six times and commissioned successfully. The fourth cooling down campaign was finished in August,2008 . This cooling down was different from the formers. Last three time cooling down campaigns were made by 4 turbines (turbine A, B,C and D), the turbine B,C and D were used to get liquid helium to cool the PF coils, TF coils, the 5 & 8 pairs current leads and buslines to the certainty temperature, and the turbine A was used to cool the thermal shield. Otherwise, the fourth cooling down is by 3 turbines (turbine A,B and C), the turbine B&C were to get liquid helium to cool the Toroidal Field (TF) magnets and Poloidal Field (PF) magnets and buslines to the certainty temperature, the turbine A was also to cool the thermal shield. In the fourth campaign it took about 20 days to cool all the coil from room temperature to liquid helium temperature.The starting-up process of turbine, magnet-cooling process and some experiment were given .