The sinking depth of a projectile in granular media under gravity
重力驱动下运动物体在颗粒介质中的最大穿透深度

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.