摘要
为了抑制入射脉冲弥散效应,采用动力有限元软件分析了常规分离式霍普金森压杆(SHPB)入射脉冲几何弥散的空间变化规律,发现入射杆中沿着应力波传播方向,几何弥散效应趋于增强;横截面上沿径向向外弥散效应趋于减弱。为此,在撞击杆的碰撞端部挖去一个共轴圆锥,称改造后的撞击杆为空心锥撞击杆。进而分析了空心锥撞击杆获得入射脉冲几何弥散的空间变化规律,结果表明:入射脉冲初始振荡得到有效抑制,且加载上升时间变长,空心锥的底面半径越大、锥角越小对弥散效应抑制效果越好;研究还发现采用空心锥撞击杆时,碰撞端面的摩擦效应对入射脉冲几何弥散影响不大,只是改变了振荡波的相位。最后,采用实验方法对该种改造方法的效果进行了验证,实验结果与理论和数值分析结果吻合较好。
In order to reduce the dispersion of incident pluse, the geometric dispersion of incident pulse of conventional split Hopkinson pressure bar（SHPB） were analyzed with dynamic finite element software. It was found that the geometric disperse became intensive along the direction of stress wave propagation, and weakened from center to outside surface. Then, a hollow cone was made coaxially in the end of solid cylindrical impact bar, and the modified bar was called as the hollow cone impact bar. Its effect on the incident pulse dispersion was studied numerically. The results show that the rise-time of incident pulse becomes large, and the geometric dispersion reduces more obviously with the larger cone radius and the smaller cone angle; the frictional effect between the impact bar and incident bar may be negligible, but the phase of oscillation is changed. The effect of modified bar was proved experimentally. The experiment results agree with the theoretical analysis and numerical simulation better.
出处
《兵工学报》
EI
CAS
CSCD
北大核心
2012年第11期1346-1351,共6页
Acta Armamentarii
基金
高等学校博士学科点专项基金(20092304110003)
中央高校基本科研业务费专项资金项目(HEUCFZ1128
HEUCF100211)
关键词
固体力学
分离式霍普金森压杆
几何弥散效应
空心锥撞击杆
入射脉冲
波形整形
solid mechanics
split Hopkinson pressure bar
geometric dispersion effect
hollow-conestriker bar
incident pulse
waveform shaping
