Theoretical and experimental investigation of magnetic field related helium leak in helium vessel of a large superconducting magnet

被引:1
作者
Bhattachryya, Pranab [1 ,2 ]
Gupta, Anjan Dutta [1 ,2 ]
Dhar, S. [3 ]
Sarma, P. R. [2 ]
Mukherjee, Paramita [1 ,2 ]
机构
[1] Variable Energy Cyclotron Ctr, 1-AF, Kolkata 700064, India
[2] Homi Bhabha Natl Inst, Bombay 400094, Maharashtra, India
[3] Jadavpur Univ, Kolkata 700032, India
关键词
Superconducting magnets - Cyclotrons - Helium - Superconducting coils;
D O I
10.1016/j.cryogenics.2017.03.005
中图分类号
O414.1 [热力学];
学科分类号
摘要
The helium vessel of the superconducting cyclotron (SCC) at the Variable Energy Cyclotron centre (VECC), Kolkata shows a gradual loss of insulation vacuum from 10(-7) mbar to 10(-4) mbar with increasing coil current in the magnet. The insulation vacuum restores back to its initial value with the withdrawal of current. The origin of such behavior has been thought to be related to the electromagnetic stress in the magnet. The electromagnetic stress distribution in the median plane of the helium vessel was studied to figure out the possible location of the helium leak. The stress field from the possible location was transferred to a simplified 2D model with different leak geometries to study the changes in conductance with coil current. The leak rate calculated from the changes in the leak geometry was compared with the leak rate calculated from the experimental insulation vacuum degradation behavior to estimate the initial leak shape and size. (C) 2017 Elsevier Ltd. All rights reserved.
引用
收藏
页码:1 / 6
页数:6
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