volume | PIER Journals

Abstract

The armature and rail sizes of electromagnetic rail launcher vary greatly, and the refined 3D finite element computation occupies a large amount of physical memory. In order to enhance the economy of dynamic computation, this paper proposes an adaptive hexahedral mesh method based on mesh expansion, compression and translation. In addition, split nodes are used on both sides of the contact surface, and interface conditions and frictional heat sources are constrained through point penalty function method to solve non-ideal sliding electrical contact problems. Comparative calculations with the same type of software and the same model are carried out, and the results calculated in this paper are consistent with the relevant results of MEAP3D. This paper also compares the EMRL calculation results of adaptive mesh model and constant mesh model to verify the reliability of the method. In addition, the C-type EMRLs are compared and analyzed. The results show that due to the influence of velocity skin effect, the dynamic inductance gradient of the rail gradually increases over time and is greater than the static value. The maximum difference between the two is 5.65% of the dynamic inductance gradient. The steel shell generates eddy currents, causing a decrease in armature velocity of 4.7 m/s under the small caliber launcher. The maximum eddy current density waveform of the shell exhibits two peaks. In the frictionless heat, the temperature of the armature is underestimated, and under the action of frictional heat, the trailing edge of the armature is ablated and melted.

1. Keshtkar, Asghar, Leila Gharib, Mohammad Sajjad Bayati, and Mohammadhosain Abbasi, "Simulation of a two-turn railgun and comparison between a conventional railgun and a two-turn railgun by 3-D FEM," IEEE Transactions on Plasma Science, Vol. 41, No. 5, 1392-1397, 2013. Google Scholar

2. Xing, Yan-Chang, Qing-Ao Lv, Bin Lei, Hong-Jun Xiang, Ren-Gui Zhu, and Chao Liu, "Analysis of transient current distribution in copper strips of different structures for electromagnetic railgun," IEEE Transactions on Plasma Science, Vol. 43, No. 5, 1566-1571, 2015. Google Scholar

3. Li, Chengxian, Lixue Chen, Zengji Wang, Jinghui Ruan, Pengfei Wu, Junjia He, and Shengguo Xia, "Influence of armature movement velocity on the magnetic field distribution and current density distribution in railgun," IEEE Transactions on Plasma Science, Vol. 48, No. 6, 2308-2315, 2020. Google Scholar

4. Li, Shizhong, Jun Li, Shengguo Xia, Qingxia Zhang, and Peizhu Liu, "Phase division and critical point definition of electromagnetic railgun sliding contact state," IEEE Transactions on Plasma Science, Vol. 47, No. 5, 2399-2403, 2019. Google Scholar

5. Sun, Jian, Junsheng Cheng, Qiuliang Wang, Ling Xiong, Yuantao Cong, and Yichen Wang, "Numerical simulation of melt-wave erosion in 2-D solid armature," IEEE Transactions on Plasma Science, Vol. 50, No. 4, 1032-1039, 2022. Google Scholar

6. Stefani, Francis and Jerald V. Parker, "Experiments to measure gouging threshold velocity for various metals against copper," IEEE Transactions on Magnetics, Vol. 35, No. 1, 312-316, 1999. Google Scholar

7. Lu, Junyong, Xiaokang Wu, Sai Tan, Yongsheng Zhang, and Bai Li, "An initial survey of the life of rail for electromagnetic launch," IEEE Transactions on Plasma Science, Vol. 47, No. 5, 2228-2232, 2019. Google Scholar

8. Sun, Jian, Junsheng Cheng, Qiuliang Wang, Ling Xiong, Yuantao Cong, and Yichen Wang, "Research on arc suppression parameter matching of augmented electromagnetic launcher," IEEE Transactions on Plasma Science, Vol. 49, No. 12, 3988-3993, 2021. Google Scholar

9. Schneider, Markus, D. Eckenfels, and S. Nezirevic, "Doppler-radar: A possibility to monitor projectile dynamics in railguns," IEEE Transactions on Magnetics, Vol. 39, No. 1, 183-187, 2003. Google Scholar

10. Meger, Robert A., Richard L. Cairns, Scott R. Douglass, Brett Huhman, Jesse M. Neri, Carl J. Carney, Harry N. Jones, Khershed Cooper, Jerry Feng, Todd H. Brintlinger, et al. "EM gun bore life experiments at naval research laboratory," IEEE Transactions on Plasma Science, Vol. 41, No. 5, 1533-1537, 2013. Google Scholar

11. Motes, D., J. Keena, K. Womack, F. Stefani, and M. Crawford, "Thermal analysis of high-energy railgun tests," IEEE Transactions on Plasma Science, Vol. 40, No. 1, 124-130, 2012. Google Scholar

12. Nie, J.-X., J.-J. Han, Q.-J. Jiao, Z.-X. Jin, and F. Zhang, "Effect of rail-type electromagnetic launcher dimensions on inductance gradient," High Voltage Engineering, Vol. 36, No. 3, 728-732, 2010. Google Scholar

13. Keshtkar, A., "Effect of rail dimension on current distribution and inductance gradient," IEEE Transactions on Magnetics, Vol. 41, No. 1, 383-386, 2005. Google Scholar

14. Gong, Fei and Chunsheng Weng, "3-D numerical study of meltwave erosion in solid armature railgun," High Voltage Engineering, Vol. 40, No. 07, 2245-2250, 2014. Google Scholar

15. Shvetsov, Gennady A. and Sergey V. Stankevich, "Comparison between 2-D and 3-D electromagnetic modeling of railgun," IEEE Transactions on Magnetics, Vol. 45, No. 1, 453-457, 2009. Google Scholar

16. Shvetsov, Gennady A. and Sergey V. Stankevich, "Three-dimensional numerical simulation of the joule heating of various shapes of armatures in railguns," IEEE Transactions on Plasma Science, Vol. 39, No. 1, 456-460, 2011. Google Scholar

17. Hsieh, K., "A lagrangian formulation for mechanically, thermally coupled electromagnetic diffusive processes with moving conductors," IEEE Transactions on Magnetics, Vol. 31, No. 1, 604-609, 1995. Google Scholar

18. Hsieh, Kuo-Ta, "Hybrid FE/BE implementation on electromechanical systems with moving conductors," IEEE Transactions on Magnetics, Vol. 43, No. 3, 1131-1133, 2007. Google Scholar

19. Lin, Qinghua and Baoming Li, "Field-circuit coupled analysis of a series-augmented electromagnetic railgun," IEEE Transactions on Plasma Science, Vol. 48, No. 6, 2287-2293, 2020. Google Scholar

20. Lin, Qinghua and Baoming Li, "Modeling and simulation of electromagnetic railgun launching process based on a transient multi-physical field solver," Acta Armamentarii, Vol. 41, No. 9, 1697-1707, 2020. Google Scholar

21. Wang, Gang-Hua, Long Xie, Yong He, Sheng-Yi Song, and Jun-Jie Gao, "Moving mesh FE/BE hybrid simulation of electromagnetic field evolution for railgun," IEEE Transactions on Plasma Science, Vol. 44, No. 8, 1424-1428, 2016. Google Scholar

22. Satapathy, Sikhanda and Kuota Hsieh, "Jump conditions for Maxwell equations and their consequences," AIP Advances, Vol. 3, No. 1, 012120, 2013. Google Scholar

Dr. Jian Sun

Dr. Junsheng Cheng

Dr. Ling Xiong

Dr. Yuantao Cong

Mr. Heyang Wang