枪弹冲击防弹头盔致头部非贯穿性损伤的数值模拟研究

Simulation of Non-penetrating Damage of Head due to Bullet Impact to Helmet

新型防弹头盔虽能对头部提供良好的保护,但也常引起颅骨骨折与脑损伤。防弹头盔在高速弹体冲击下引起的头部非贯穿性损伤的机理难以理解,目前还缺少相应的参数与测试方法对该类损伤进行有效评估。利用已建立及通过验证的人体头部生物力学模型与防弹头盔有限元模型,并通过加载手枪弹以386 m/s的速度冲击防弹头盔的仿真研究,获得头盔非贯穿下人体头部的生物力学响应。仿真结果表明,头盔通过背面变形接触头部易引起颅骨骨折与高颅内压力。对比分析了有无衬垫泡沫及6 mm和12 mm泡沫内饰衬垫厚度对头部损伤的影响:有泡沫作用下的颅内压力峰值降低20.6%,头盔的背面变形量减少约10%;6 mm厚衬垫泡沫作用下颅骨出现骨折,12 mm厚衬垫泡沫作用下颅内压力峰值减少50%,头盔的背面变形减少10%.

New ballistic helmet can provide good protection for human head. The head injury caused by ballistic impact has not been well understood. There is a lack of relevant test procedure to evaluate the efficiency of a ballistic helmet. The head model is validated against several impact tests on cadavers, and the helmet model is validated against data from shooting tests. The mechanical response of the helmet to the human head under non-penetration of helmet is obtained through the simulation of the ballistic helmet with 386 m/s impact speed of bullet. The simulated results show that the deformation of the back of helmet can lead to skull fracture and high intracranial pressure. The influences of helmets with and without foam pad, as well as foam pad thickness on the head injury are compared and analyzed. The results show that, by using the helmet with foam pad, the intracranial pressure of head wearing a helmet with foam poad is reduced by 20.6% , and the deformation of helmet with foam poad is reduced by 10%. The skull was still under high-risk of skull fracture with 6 mm foam pad. With 12 mm foam pad, the intracranial pressure is decreased by 50% , and the deformation of the back of helmet is decreased by 10%.