论文标题
带有粗粒离散元素模型的粘合剂磨损
Adhesive wear with a coarse-grained discrete element model
论文作者
论文摘要
分子动力学（MD）模拟的使用导致了有希望的结果，以揭示粘合剂磨损的原子源，尤其是在纳米级表面浅层处的磨损开始。但是，MD模拟具有高计算成本，并仅提供狭窄的时间和长度尺度范围。我们在这里建议求助于离散元素方法（DEM），以减轻计算成本。使用具有接触和凝聚力的DEM颗粒，我们重现了使用MD观察到的关键机制，同时具有颗粒直径和系统大小的数量级比MD高。对成对力进行调整以获得具有合理近似弹性和断裂特性的固体。使用范围粒径成功地复制了用MD进行的单腹部磨损的模拟，从而验证了粗粒度的过程。更复杂的模拟应允许研究磨损颗粒和粘合剂磨损环境中磨损表面的演变，同时达到MD无法接近的尺度。
The use of molecular dynamics (MD) simulations has led to promising results to unravel the atomistic origins of adhesive wear, and in particular for the onset of wear at nanoscale surface asperities. However, MD simulations come with a high computational cost and offer access to only a narrow window of time and length scales. We propose here to resort to the discrete element method (DEM) to mitigate the computational cost. Using DEM particles with contact and cohesive forces, we reproduce the key mechanisms observed with MD, while having particle diameters and system sizes an order of magnitude higher than with MD. The pairwise forces are tuned to obtain a solid with reasonably approximated elastic and fracture properties. The simulations of single asperity wear performed with MD are successfully reproduced with DEM using a range particle sizes, validating the coarse-graining procedure. More complex simulations should allow the study of wear particles and the evolution of worn surfaces in an adhesive wear context, while reaching scales inaccessible to MD.
