异形多级颗粒模型的数值模拟试验与破碎实验

Numerical simulation test and crushing experiment of multi-stage particle models with deferent shape

针对3种形状的岩石样本进行3D扫描,得到岩石外形的云点数据,构建了异形岩石几何模型;结合高倍显微镜观测的岩石岩相,定义了岩石颗粒间的粘结模型和接触模型,建立了异形多级颗粒的力学模型;基于EDEM软件,在振动慢剪破碎试验机上进行数值模拟试验,并统计岩石破碎后的岩石产率。经与破碎实验结果对比分析后的结果表明:岩石粒度分别在<4、<8、≥8 mm时,数值模拟试验与破碎实验得到的岩石产率与外锥转速的关系曲线趋势基本一致;破碎机在外锥转速为45 r/min、内锥频率为40 Hz时岩石产率最大、破碎效果最佳;数值模拟试验与破碎实验的相关系数分别为0. 95、0. 97和0. 97,建立的异形多级颗粒模型能够较好地模拟岩石破碎机理。

3D scanning was carried out on rock samples of three shapes to obtain cloud point data of rock shape and the geometric models of shaped rock were constructed. Combining with the lithofacies observed by high power mirror,the bonding model and contact model of rock particles were defined and the mechanical models of multi-stage particle with deferent shape were established.Based on EDEM software,the numerical simulation test was carried out on the vibration slow shear crushing machine and the rock yield after rock crushing was calculated.Compared with the results of crushing experiments,the results show that the trends of relationship curve between rock yield and external cone speed are basically consistent when the sizes of particles obtained by numerical simulation test and crushing test of rock are less than 4,less than 8 and greater than or equal to 8 mm.Rock yield is the highest and crushing effect is the best when the outer cone speed is 45 r/min and the inner cone frequency is 40 Hz.The correlation coefficients between numerical simulation test and crushing experiment are 0.95,0.97 and 0.97 respectively.Therefore,Multi- stage particle model with deferent shape established can well simulate the mechanism of rock crushing.