本研究探討了雷射粉床熔融(laser powder bed fusion, LPBF)腔體內的氣流、噴濺的即時量測和顆粒流體間的模擬。流場分別藉由實驗上用熱線風速計，模擬中用計算流體力學(computational fluid dynamics, CFD)的方法被量化，計算流體力學則是運用了Fluent軟體。模擬的結果由實驗驗證後，得到平均為37.6 %的誤差。在實驗和模擬中都能看出，從40.5到20.5毫米的高度，風速隨著高度的降低而變快。
　　噴濺通常被用來指稱在雷測粉床熔融製程中從熔池內噴出或在掃描軌跡附近被挾帶，所有固態且對製程有害的副產物。為了要觀察噴濺的運動情形，需要進行LPBF的實驗，粉末材料為英高鎳基合金(Inconel 718)，同時架設高速攝影機。在記錄下噴濺的動態影片後，在噴濺一開始噴出時，他們的初始條件和顆粒大小會藉由影像處理的方法被量測出。量測到的初始速度大小、初始角度和顆粒大小與文獻中的數值比較結果顯示這些數據足夠準確，足以能被代入到計算流體力學和離散元素法(computational fluid dynamics-discrete element method, CFD-DEM)的耦合模擬中，作為初始條件。
　　藉由Fluent和EDEM兩個軟體，CFD-DEM模擬能被用來研究噴濺動力學，而文獻被用作參考，以檢視此模擬模型的有效性。由最大噴濺距離和最大噴濺高度，文獻和模型的比較結果顯示模型在計算顆粒的軌跡和落點上是準確的。另外，將模型與製程實驗比較發現大量大顆的噴濺會落在離熔融工件較近的位置，而少量大顆的噴濺會落在離熔融工件較遠的位置。

The research studied the gas flow inside the chamber of Tongtai AM-250 laser powder bed fusion (LPBF) machine, in-situ measurement of spatters, and particle-fluid simulation. The flow field was quantified both experimentally and numerically by means of hot-wire anemometer and computational fluid dynamics (CFD) by Fluent software, respectively. The results of simulations validated with those of experiments, and the error has an average of 37.6 %. In both experiment and simulation, flow velocity increases with the decrease of height from 40.5 to 20.5 mm.
Spatter is a collective term specializing all solid and hazardous by-products ejecting from the melt pool or entrained from the vicinity of melt track during LPBF process. To observe the motion of spatters, LPBF experiments were carried out with material Inconel 718 and with the installation of high-speed camera meanwhile. After recording the movement of spatters, initial conditions, and size of them were measured right at the time of ejection. The initial velocity, angle, and size were validated against the data in literatures, and those data are sufficiently accurate to be imported into CFD-DEM (computational fluid dynamics-discrete element method) simulation.
By both Fluent and EDEM softwares, dynamics of spatters was studied in CFD-DEM simulation. Literatures were taken reference from to inspect the validity of the model. By using maximum ejection distance and maximum ejection height as indicators, the comparisons showed that the simulation model is accurate on calculating the trajectories and landing sites of spatters. Furthermore, by comparing the model with the LPBF experiment, the trend was found in both that more number of large spatters land near the scan, while less number of large spatters land on the powder bed farther away from the scan.

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