物料冲击破碎过程的一种非线性力模型

NONLINEAR FORCE MODEL DURING MATERIAL'S IMPACT CRUSHING

针对冲击破碎过程,在初步准静压破碎实验的基础上,提出了物料层的分段线性接触力模型,并引入恢复系数来表示膨胀阶段和压缩阶段之间的参数关系。应用该模型进行了单球冲击破碎的计算机模拟,证明恢复系数能宏观反映冲击破碎过程的能量损失。与线性弹簧阻尼模型相比,不但在微观过程中接触力保持正压,物料破碎会产生不可恢复的变形,更符合实验观察的实际情况,而且计算精度更高。

The piecewise linear contact force model of material layers during impact crushing is put forward, based on the quasi-static compression crushing experiments, in which the parameters of model are analyzed and a revert coefficient is introduced to express the relation between parameters. Applying the contact force model to the numerical simulation of single-sphere impact crushing, it is verified that the revert coefficient can express the energy loss during impact crushing, and the computed micro-force and micro-deflection accord with the experiment observations, with plus-compression force in contact and irreversible deflection resulted from material crushing.