摘要
本文对旋转盘式间接杆杆型冲击拉伸试验装置建立了产生拉伸加载脉冲的三维弹塑性动力学模型 ,使用ANSYS/LSDYNA程序模拟了该装置产生加载脉冲的过程 ,分析了弹塑性材料的滤波作用。数值模拟得到的入射脉冲与实验结果吻合 ,表明该数值模型和方法是有效的。分析结果表明 ,相对于直接连接系统 ,间接连接系统中的前置金属短杆的弹塑性变形直至断裂使锤头与撞块只发生一次撞击 ,即滤去了多次撞击 ,同时滤去了金属短杆与撞块界面扰动力的高幅抖动 ,使扰动力变成幅值较低的平稳脉冲。总之 ,前置金属短杆的作用相当于一个低阈值的低通滤波器。
A 3D elastic-plastic dynamic finite element model for the generation of the incident pulse in the rotating disk indirect bar-bar tensile impact apparatus was established in the present paper. The numerical simulation was solved by ANSYS/LSDYNA. The filter function of elastic-plastic material was illuminated. The numerical results are in good agreement with those from experiments. Therefore the availability of the model and the method are evaluated. Compared to the direct connection system, the numerical analysis shows that the elastic-plastic deformation till fracture of the short metal bar in the indirect connection system makes the hammer impact the block only one time. It filters multiple times of impact and the strong oscillation of the incident pulse, so the pulse is rather stable. In a word, the function of the prefixed short metal bar is equivalent to a filter with a low threshold. The numerical model and method in present paper could be used as the basis of selecting rational experimental scheme, improving and designing new kind of tensile impact test apparatus.
出处
《实验力学》
CSCD
北大核心
2004年第4期469-476,共8页
Journal of Experimental Mechanics
