Mixing is an essential manufacturing process in various industries. The processing procedure and final product quality depend on the homogeneity of mixing. Because it is difficult to evaluate mixing systems experimentally, the discrete element method is commonly employed. However, as the number of particles increases, this approach incurs huge computational costs. The coarse grain model offers a potential solution, but its applicability has not been widely demonstrated; this study aimed to elucidate the upper limit for applying the coarse grain model. To determine the appropriate simulation parameters, calibrations were performed by comparing the powder bed in experiments versus simulations. Various mixing processes were numerically evaluated, and the mixing characteristics were qualitatively consistent among all coarse-grained ratios. These mixing systems were also evaluated quantitatively based on Lacey’s mixing index, which indicated that the upper limit of the coarse-grained ratio was five times. It is therefore important to secure a sufficient number of particles in each cell and to use an appropriate number of cells. This study clarified the upper application limit and criteria for the coarse grain model and verified the maximum coarse-grained ratio (five times). This approach can be used to determine the coarse-grained ratio and reduce computational costs.

混合是各个行业必不可少的制造过程。加工程序和最终产品质量取决于混合的均匀性。由于很难通过实验评估混合系统，因此通常采用离散元方法。然而，随着粒子数量的增加，这种方法会产生巨大的计算成本。粗粒模型提供了一种潜在的解决方案，但其适用性尚未得到广泛证明；本研究旨在阐明应用粗晶粒模型的上限。为了确定合适的模拟参数，通过比较实验和模拟中的粉末床来进行校准。对各种混合过程进行了数值评估，所有粗粒比例的混合特性在质量上是一致的。还根据莱西混合指数对这些混合系统进行了定量评估，该指数表明粗粒比的上限为五倍。因此，确保每个单元中有足够数量的粒子并使用适当数量的单元非常重要。本研究明确了粗晶模型的应用上限和标准，并验证了最大粗晶比（5倍）。这种方法可用于确定粗粒度比率并降低计算成本。本研究明确了粗晶模型的应用上限和标准，并验证了最大粗晶比（5倍）。这种方法可用于确定粗粒度比率并降低计算成本。本研究明确了粗晶模型的应用上限和标准，并验证了最大粗晶比（5倍）。这种方法可用于确定粗粒度比率并降低计算成本。