碎片云SPH方法数值模拟中的材料失效模型

The smoothed particle hydrodynamics (SPH) method is widely used in debris cloud simulation under hypervelocity impact. The SPH solver in AUTODYN was employed to investigate the effects of the no-failure model, the Grady failure model and the maximum tension failure model on the simulation results of debris cloud. When using the no-failure model, the simulation result and material response were not consistent with the experiment. Compared with the Grady model, the material under the maximum tension model was more difficult to fail, which would slightly weaken the expansion of debris cloud, produce less but heavier debris because of particles gathering, and thus improve the penetration performance of debris cloud. Similarly, by increasing the failure stress threshold, the above result was also obtained. Considering the material response and debris distribution, the simulation result by the Grady model was closer to the experiment. However, the difference between the Grady model and the maximum tension model was related to the impact condition, and more complete fragmentation of the material would lead to a smaller difference.