The present work deals with the numerical prediction of the particle flow within a three-way nozzle in Laser Metal Deposition (LMD) technology adopted during additive manufacturing processes. In particular, the paper focuses on CFD (Computational Fluid Dynamics) simulations of the particle flow problem, regarding the coupling between a fluid phase, i.e., the carrier gas, and a solid phase, i.e., a metallic material powder that is delivered through the nozzle of the LMD machine.

Two different numerical approaches are investigated, both implemented in a in-house code using OpenFOAM open source C++ toolbox. The former is based on a mixed formulation, combining an Eulerian description of the carrier gas flow with a Lagrangian description of the particle flow. The latter on a pure Eulerian formulation of both carrier gas and particles.

In agreement with the experimental evidences, the present work compares the two approaches in terms of capability of simulating some key physical features of the LMD process, i.e., the geometrical properties of the powder cone formed out from the nozzle.

目前的工作涉及在增材制造过程中采用的激光金属沉积 (LMD) 技术中三通喷嘴内粒子流的数值预测。特别是，该论文侧重于粒子流问题的 CFD（计算流体动力学）模拟，关于流体相i之间的耦合。例如，载气和固相i . 例如，通过 LMD 机器的喷嘴输送的金属材料粉末。

研究了两种不同的数值方法，均使用 OpenFOAM 开源 C++ 工具箱在内部代码中实现。前者基于混合公式，将载气流的欧拉描述与粒子流的拉格朗日描述相结合。后者基于载气和粒子的纯欧拉公式。

在与实验依据协议，目前的工作在模拟过程LMD的一些关键物理特点，能力方面的两种方法比较我。例如，从喷嘴形成的粉末锥体的几何特性。