摘要
电磁轨道发射器轨道表面裂纹引起的磁锯现象严重制约着发射器的使用寿命。为了更好地分析这种现象,建立了二维情况下的磁扩散方程和热传导方程。结合有限元软件COMSOL Multiphysics中的固体力学模块,对轨道表面裂纹处的电磁、热和力学行为进行了仿真分析。求解过程考虑了材料参数随温度的变化。结果表明,电流在裂纹处"绕行",引起尖端局部电流密度过大是导致磁锯效应的重要原因。加载电流峰值为0.8 MA时,裂纹尖端处最大电流密度可达1010 A/m2量级。此外,对裂纹形状的分析表明,裂纹尖端张角越小,电流的聚集现象越严重,产生的温升也越大。
Magnetic sawing phenomenon, induced by the crack in the rail of the electromagnetic launcher, can severely re- strict the life of the launcher. To analyze this phenomenon, we built the magnetic field diffusion equation and heat conduction e- quation. Combined with the solid mechanics model in the finite element software COMSOL Multiphysics, we simulated the elec- tromagnetic, thermal and mechanical behaviors of the crack. The results show that the current-crowding as the current path turns around the crack tip is a key {actor for the formation of magnetic sawing phenomenon. Moreover, we found that, the smaller the aperture angle, the higher the current density, the faster temperature rises.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2015年第6期247-252,共6页
High Power Laser and Particle Beams
基金
国家自然科学基金项目(51237007)
关键词
电磁轨道发射器
裂纹
有限元
磁锯效应
电流密度
electromagnetic launcher
crack
finite element
magnetic sawing effect
current density
