顆粒流對垂直平板撞擊力之數值模擬

張欽舜(CHIN-SHUN CHANG)

指導教授 ： 周憲德

國立中央大學/工學院/土木工程學系/碩士(2014年)

摘要

撞擊力為土石流運動破壞結構物的重要因素之一。本研究在窄渠道內進行顆粒流崩塌模擬，並分析其流動物理特性及堆積機制，為了解顆粒流內部力量傳遞到板子上過程，使用PFC-3D程式進行數值模擬；數值模擬部分則以聚苯乙烯顆粒為模擬，並在底部黏上粗糙層顆粒，而堆積塊體高寬比a( )=1.4、顆粒填充高度Hf度作為主要對比參數，首先以模擬單顆粒試驗方式輸入參數的正確性，進而以撞擊力及塊體堆積等方式探討撞擊力對側板之影響。
本研究在PFC-3D數值模擬部分主要觀察其撞擊力、內部接觸力、不平衡力、動能、摩擦損耗之變化，其分析是以堆積高度、撞擊力變化、堆積型態為主。撞擊力變化在板距20cm情形最大撞擊力為0.7N、側板距30cm最大撞擊力為0.2N。

關鍵字

顆粒流 ； 崩塌 ； 離散元素法 ； 撞擊力

並列摘要

In this study, the impact forces acting on vertical walls by collapsing granular piles. DEM is explored by employing simulation PFC-3D. In the PFC-3D simulation, the observed impact force, inside contact force, unbalanced force, kinetic energy, friction energy loss are examined with different granular pile heights and wall location. The effect of stacking types and deposition are studied impact forces. In the PFC-3D numerical simulation found in the overall physical flow behavior is similar. The maximum impact force is 0.7N dependent on the
wall location.

並列關鍵字

Granular flows ； Collapse ； DEM ； impact force ； PFC-3D

參考文獻

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