顆粒崩塌流場普遍存在於工業界、自然界或是日常生活中。工業界中包括如儲槽 (hopper) 及旋轉鼓 (rotating drum) 等，而自然界中如雪崩、山崩或土石流等災害也可列為顆粒流的一環。故此類顆粒崩塌流場的相關學術研究於近年來備受重視，也越來越多學者發表相關研究成果。本論文主要以線性軟球模式的離散元素法 (Discrete element method, DEM) 來模擬在傾斜矩形流槽中，由重力所驅動之顆粒崩塌流場的運動行為。本論文將採用Particle Flow Code in 3D 模擬軟體，並利用不同控制參數去探討各阻礙物對顆粒崩塌流場的運動行為及相關物理機制之影響。本論文中，為讓流場產生劇烈變化，將在流槽中設置不同半徑的半圓柱形阻礙物，使流場中產生震波，探討不同阻礙物大小對於整體流場的影響，包括流場高度、流場速度、顆粒體積佔有率、旋轉角速度、配位數(coordination number)、顆粒接觸力、慣性數(inertial number)、組構及組構張量(fabric tensor)八個分析指標在流動方向的變化及相關物理機制。

Granular avalanches flows are widely found in nature and industrial applications. In industrial applications, they can be found as hoppers and rotation drums and, in the nature, they are in the form of avalanches, landslides, mudflows. Granular flows have received significant attention by researchers and scholars. This study is performed based on a linear soft-sphere model discrete element method (DEM) has been used to simulated performance of granular flow driven by the gravity in an inclined rectangular chute. DEM calculations were done by using commercial simulation software called PFC3D. An inclined rectangular chute was set up by using different control parameter in order to analysis and evaluates the overall flow performance. Additionally, in order to simulate changes in the flow fields were establishment in a different semi-circular cylinder obstacle radius of the chute to generate shock waves. It allowed exploring and analyzing the flow field in different size of obstructions that were affecting the overall field which included flow height, flow velocity, solid fraction, angular velocity, coordination number, contact force, fabric and fabric tensor.

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