中国物理B ›› 2013, Vol. 22 ›› Issue (8): 84102-084102.doi: 10.1088/1674-1056/22/8/084102

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Ablation and geometry change study of solid armature in a railgun

张亚东, 阮江军, 胡元潮, 龚若涵, 文武   

  1. School of Electrical Engineering, Wuhan University, Wuhan 430072, China
  • 收稿日期:2012-10-27 修回日期:2012-12-29 出版日期:2013-06-27 发布日期:2013-06-27
  • 基金资助:
    Project supported by the National Basic Research Program of China (Grant No. 2011CB209404) and the Post-doctoral Science Foundation of China (Grant No. 2012M521465).

Ablation and geometry change study of solid armature in a railgun

Zhang Ya-Dong (张亚东), Ruan Jiang-Jun (阮江军), Hu Yuan-Chao (胡元潮), Gong Ruo-Han (龚若涵), Wen Wu (文武)   

  1. School of Electrical Engineering, Wuhan University, Wuhan 430072, China
  • Received:2012-10-27 Revised:2012-12-29 Online:2013-06-27 Published:2013-06-27
  • Contact: Wen Wu E-mail:wenwu654321@163.com
  • Supported by:
    Project supported by the National Basic Research Program of China (Grant No. 2011CB209404) and the Post-doctoral Science Foundation of China (Grant No. 2012M521465).

摘要: Armature plays an important role in the electromagnetic launch process. Due to the skin effect, the current density distribution is neither uniform on the rail, nor on the armature. High current density centralization in one part could lead to a partial high temperature and make the armature material melt down and be ablated, especially at low velocity. In this paper we try to change the geometry of a Cshaped armature to improve the current density distribution and reduce the ablation. Four variants of C-shaped armatures are designed to study the specific features, including a conventional C-shaped armature (CCA), a rounded leading edge C-shaped armature (LCA), a rounded trailing edge C-shaped armature (TCA), and a rounded incorporate edge C-shaped armature (ICA). A novel low-speed experiment is constructed and tested. The armatures are ablated and recovered to compare the improved effects. Then finite element simulations according to the experimental results are performed to further analyze the experimental results. It is proved that the current density and hence the temperature distribution can be immensely improved by simply changing the armature geometry. LCA and ICA show that the erosion is more uniform on the contact surface due to the rounded leading edge. The curved trailing edge could improve the uniformity of the current on the interface. ICA which combines the effects of LCA and TCA is the best option in the four armatures. How much the leading edge and the trailing edge should be curved involves the geometry of CCA and the posture of the interface on the rail. A saddle shape is a good option to improve the current density and temperature distribution in the throat. Erosion mechanism is analyzed finally. The experiments and simulations support the erosion and transition mechanism. A detailed description of the experiments and simulations is also presented in this paper.

关键词: railgun, ablation, friction, geometric modeling

Abstract: Armature plays an important role in the electromagnetic launch process. Due to the skin effect, the current density distribution is neither uniform on the rail, nor on the armature. High current density centralization in one part could lead to a partial high temperature and make the armature material melt down and be ablated, especially at low velocity. In this paper we try to change the geometry of a Cshaped armature to improve the current density distribution and reduce the ablation. Four variants of C-shaped armatures are designed to study the specific features, including a conventional C-shaped armature (CCA), a rounded leading edge C-shaped armature (LCA), a rounded trailing edge C-shaped armature (TCA), and a rounded incorporate edge C-shaped armature (ICA). A novel low-speed experiment is constructed and tested. The armatures are ablated and recovered to compare the improved effects. Then finite element simulations according to the experimental results are performed to further analyze the experimental results. It is proved that the current density and hence the temperature distribution can be immensely improved by simply changing the armature geometry. LCA and ICA show that the erosion is more uniform on the contact surface due to the rounded leading edge. The curved trailing edge could improve the uniformity of the current on the interface. ICA which combines the effects of LCA and TCA is the best option in the four armatures. How much the leading edge and the trailing edge should be curved involves the geometry of CCA and the posture of the interface on the rail. A saddle shape is a good option to improve the current density and temperature distribution in the throat. Erosion mechanism is analyzed finally. The experiments and simulations support the erosion and transition mechanism. A detailed description of the experiments and simulations is also presented in this paper.

Key words: railgun, ablation, friction, geometric modeling

中图分类号:  (Other advanced accelerator concepts)

  • 41.75.Lx
85.70.Ay (Magnetic device characterization, design, and modeling) 85.70.Rp (Magnetic levitation, propulsion and control devices)