一种基于概率密度函数的DEM 试样生成法

离散元模拟颗粒材料力学性能时,为保证生成数值试样级配曲线的连续性以及与所需级配曲线的吻合性,基于概率密度函数法,提出一种用于制备颗粒流离散单元法数值试样的新方法。定义了级配的不匹配度参数,用来定量描述生成试样的级配曲线与原型级配曲线的偏差。对比了该方法和现有试样制备法,并讨论生成颗粒数目对生成试样级配曲线的影响。结果表明,该试样生成法能够模拟任意级配曲线的试样,且生成的数值试样级配曲线具有良好的连续性和光滑性。随着生成颗粒数目的增大,该试样生成法生成的试样级配曲线收敛于原型试样级配曲线。

A specimen generation method for discrete element method based on probability density function

During the simulation of material mechanical properties of granular materials using the discrete element method(DEM), in order to guarantee the continuity of the generated grading curve for the numerical specimen and the conformity of the generated grading curve with the desired grading curve, a new method based on the probability density function (PDF) was proposed to generate a numerical specimen of the particle flow DEM. A parameter to describe the mismatch of grading was defined to quantify the deviation between the generated grading curve and the original grading curve. A comparison of the proposed method and the existing method of specimen generation was conducted and the influence of the particle number on the generated grading curve was investigated. The results show that the proposed method can generate specimens of an arbitrary grading curve and the generated grading curve has a high degree of continuity and smoothness. Moreover, as the number of generated particles increases, the generated grading curve based on the PDF converges to the original grading curve.