中文摘要：

通过高速摄像的跟踪，研究了重力场中球形下落物体对松散颗粒床进行撞击并进入颗粒床内的运动过程．运用已得到的颗粒体系中运动物体的阻力模型，分析了物体质量对穿透深度的影响．研究表明，当物体与颗粒床撞击的初始速度较小时，物体在颗粒床中的最大穿透深度与物体质量呈近似线性关系．实验得到的结果与模型符合很好．

英文摘要：

The process of impact and penetration of a projectile with velocity u0 in a fine, loose granular system under acceleration due to gravity has been recorded experimentally by using fast video photography. The measured penetration depth as a function of the projectile mass agrees with the prediction of our previous drag force model in that at low impact velocity the penetration depth is linearly proportional to the mass of the projectile.