ALE方法分析爆炸载荷作用下圆板动力反直观行为

运用ANSYS/LS-DYNA软件对TNT炸药爆炸后,空气冲击波作用下弹塑性圆板的动力反直观行为进行了数值模拟. 采用任意拉格朗日-欧拉算法(ALE算法),将炸药、空气和板进行有限元离散,在考虑材料屈服极限及应变率效应对动力反直观行为影响的情况下,分别取全模型和1/4模型进行比较. 结果表明,用ALE流-固耦合方法研究爆炸载荷作用下结构反直观行为是行之有效的;材料性能、板厚度对动力反直观行为有较大影响,只有材料的屈服极限较低且厚度较薄的板,容易发生反直观行为;同时,在数值分析时需要考虑应变率的效应.

Anomalous Response of a Circular Plate Under Blast Loading with the ALE Method

Anomalous response of elastic-plastic circular plate subjected to TNT air blast loading is studied using LS-DYNA as the numerical tool. TNT. air and plate are taken as varied finite elements with ALE arithmetic comparing full model and 1/4 model. Yield stress and strain rate have been considered for anomalous responses. It is found by numerical analyses that ALE arithmetic is a better method for structural anomalous dynamic behavior under blast loading. Material parameters and the thickness of the plate have influence on anomalous response. Anomalous response of the plate appeared easily when yield stress is lower and the thickness of plate thinner. Strain rate should be considered for numerical simulation of anomalous response under blast loading.