针对二维域颗粒集生成,提出一种将传统的颗粒集生成方法——构造法和动态法相结合的新算法,称之为混合法.根据颗粒下落堆积时接触的2种不同目标,分2种情形计算颗粒与目标接触之后的移动方向:当与颗粒接触时,采用纯几何方法计算新方向,即两颗粒接触点切线向下的方向,颗粒按此方向移动近似接近动态法物理规律;当与容器边界接触时,根据弹性碰撞理论计算新方向,颗粒按此方向移动符合动态法物理规律.颗粒下落堆积时的接触检测基于构造法前沿元素.最终生成颗粒集的时间与颗粒数量成线性关系,且耗时短、密度高.
A new hybrid method was proposed for sphere packing in two-dimensional region, which combined the traditional dynamic method with the traditional constructive method. The algorithm calculated the particles' moving directions with two different methods according to the two different touching objectives during the process of falling. When the touching objective was particle, the moving direction was calculated with the purely geometric-based method in which the new direction was downward along the tangential direction of the two-contact particles' touching point. The moving direction of the particle approximated the physical law of the dynamic method. When the touching objective was the boundary of the container, the new direction was calculated with the elastic collision theory, which consisted with the physical law of the dynamic method. The touch detections between particles were based on the advancing-front elements of the constructive method. The time to create the granular particles set was linear with the particle number, and this process was completed in a comparatively short time with high density particles set.