一般工程上的顆粒負載流需考量紊流場的影響，為了研究微小顆粒碰撞及結塊過程，本研究將問題簡化成於充滿靜止空氣之控制體積中加入週期性重力場以驅動顆粒運動，如此可避開流體力學因素對模擬結塊因素之影響。以乾燥的二氧化矽顆粒來進行吸附力模擬，其中考量Bradley接觸機制模式，並以Lennard-Jones模式估算碰撞過程中的吸附衝量。結塊模式的部分，以衍生硬球模式模擬結塊現象。顆粒間碰撞的部分，以雙體硬球碰撞模式模擬碰撞主導流，為了避免因顆粒分布不均勻造成多體碰撞，以平均絕對誤差和方均根測試顆粒於空間的均勻度，求得最佳的週期性重力場振幅常數，以發展顆粒間碰撞之結塊機制。
本研究設定碰撞主導流的模擬條件為顆粒體積佔有率0.0377、顆粒數為729、粒徑2 µm，模擬驗證週期性重力場常數500000 m/s2驅動顆粒的空間均勻度最佳，以此條件模擬碰撞及結塊現象，結塊數隨時間遽增，程式執行0.01秒後，結塊速率趨緩，執行至0.03秒累積的結塊數為518，剩餘的顆粒數為211；稀薄流的模擬條件為顆粒體積佔有率0.0009，其顆粒數、粒徑與碰撞主導流的設定相同，因為稀薄流的碰撞頻率小於碰撞主導流，稀薄流於程式執行0.03秒後，結塊數仍隨時間線性遞增；以週期性重力場常數5000 m/s2執行粒徑10 µm的結塊現象，其顆粒數、體積佔有率與粒徑2 µm的設定相同，模擬結果顯示以較小的週期性重力場驅動顆粒，造成顆粒間的相對速度小，亦會造成結塊現象。

Particle-laden flows are engaged with turbulence interactions, which are very complex in fluid dynamics. In order to investigate the collision and agglomeration processes for moving micro particles, a control volume in which the particles are driven by a periodic gravitational field in a quiescent environment is used in this study to avoid the complex fluid dynamics.
A contact mechanical model, Bradley model, is used to model cohesive force among dry silica particles. The Lennard-Jones model is used to evaluate the effect of the cohesive force in the collision process. In the agglomeration model, the extended hard-sphere model is used for simulation. To account for the inter-particle collisions, the binary hard-sphere collision model is used to simulate the collision-dominated flow.
In order to avoid multiple collisions among the particles, the spatial uniformity has been tested in terms of mean absolute error and root mean square. A model for the inter-particle process associated with agglomeration mechanism has been successfully developed.

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