本研究基於離散元素法的模型架構，使用數值模擬套裝軟體 EDEM 2.2，模擬不同長寬比的橢圓顆粒，在二維漏斗內部流動阻塞的影響。使用相同的體積不同長寬比(r)的橢圓顆粒群，分別有 r=1.0,2.0,2.5,3.0，每次使用固定200顆的顆粒數，從數個固定形狀且不同開口寬度的二維漏斗中流出，觀察流動阻塞行為，從中分析橢圓長寬比影響阻塞機率的趨勢。結果顯示，當橢圓顆粒長寬比愈大時，愈容易促使流動阻塞行為的發生。同時，再從模擬數據中提取分析，檢視固定開口寬度的漏斗下，當長寬比愈大時，顆粒排出漏斗的平均流率愈為緩慢。

In the present study, the EDEM simulation package, which is based on the discrete element method, is employed to study the effects of the aspect ratio on the jamming processes of a dry elliptic granular matter flowing from a two-dimensional hopper. In the simulations’ the aspect ratio is taken as the primary simulation parameter, while the volumes of the elliptic particles are kept unchanged at different aspect ratios. Numerical simulations show that the jamming probability increases as the aspect ratio increases. This is due to the facts that arching near the opening of the hopper is easier to be found in elliptic grains. In addition, it is also found that the average volume flow rate decreases as the aspect ratio increases.

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