EXPERIMENTAL STUDY ON VELOCITY DESTRIBUTION OF FRAGMENTS PRODUCED BY CATASTROPHIC IMPACTS

利用单级装药火炮和双级轻气炮对球形和立方叶蜡石进行了冲击破碎实验。获得了17个实验的高速运动影片。结果表明：1.球形目标破片的尺寸分布分为两个区域，而不是三个区域。Takagi等人指出的三个政权。(1984)可能是目标形状的影响。对最大破片质量的刻度表明，冲击波随距离的衰减率比-2晚于-3.3。碎片速度与碎片质量的明显负相关性，如Nakamura等人的结论。(1991)，没有得到遵守。破片速度与冲击点到破片初始位置的距离的-0.6次方相关。破片速度与破片初始位置的冲击波压力相关。平均破片速度与无量纲冲击应力相关。

Impact fragmentation experiments of spherical and cubic pyrophyllites were performed using a single-stage powder gun and a double-stage light gas gun. High speed motion movies of 17 experiments were obtained. The obtained results are :1. Size distribution of fragments from spherical targets are divided into two regimes, not three. The three regimes indicated by Takagi et al. (1984) may be an effect of target shape.2. The scaling on the largest fragment mass shows that the decay ratio of shock wave with distance is -2 later than -3.3. The clear negative dependence of fragment velocity on fragment mass, such as that by Nakamura et al. (1991), was not observed.4. Fragment velocities correlate with the -0.6-th power of the distance from the shock point to the initial position of fragment.5. Fragment velocities correlate with the shock wave pressure at the initial position of fragments.6. The average fragment velocities correlate with the nondimensional impact stress.