论文标题
使用高斯梁射线表示的定向能量沉积粉末流建模
Directed energy deposition powder stream modeling using a Gaussian beam ray representation
论文作者
论文摘要
可以使用粉末进料（ded-pf）机器在某些同轴喷嘴中的侧馈喷嘴或粉末流的一部分粉末流，可以使用粒子速度场进行建模，该粒子速度场与粉末流的粉末速度持续向下成分，外部成分与粉末流的中心线的成比例。但是，当粉末流受到力场的影响时，发现粉末浓度功能的形状靠近粉末流的中心在高度的聚焦程度上大大差异。通过基于高斯光束的射线表示对粉末流进行建模来减少这种差异。高速相机粒子跟踪和将轨迹推向喷嘴出口的实验结果表明，粉末流的统计数据与该模型相对应。还展示了一种新的方法，使用光学系统类似物计算沿流的颗粒浓度，而聚焦力场则模拟为分级折射率（Grin）镜头的转移矩阵。该方法比相应的拉格朗日模拟快的阶数。
The powder stream from a side feed nozzle, or part of the powder stream in some coaxial nozzles, in a directed energy deposition via powder feeding (DED-PF) machine, can be modeled using a particle velocity field that has a constant downward component and a linearly increasing outward component, in proportion to the powder stream's center line distance. However, when the powder stream is subject to a force field, it was found that the shape of the powder concentration function close to the center of the powder stream diverges considerably at high degrees of focusing. This discrepancy is reduced by modeling the powder stream based on the ray representation of a Gaussian beam. Experimental results from high-speed camera particle tracking and numerically extrapolating the trajectories to the nozzle exit suggests that the statistics of the powder stream correspond to this model. A novel method to compute the particle concentration along the stream using an optical system analog, with the focusing force field modeled as the transfer matrix of a graded refractive index (GRIN) lens, is also demonstrated. This method is orders of magnitude faster than the corresponding Lagrangian simulation.
