A Coupled Fluid-Granular Approach to Modelling Powder Stream in Directed Energy Deposition

¹ Institute of Metals and Technology, Lepi pot 11, Ljubljana, Slovenia
² Materials and Processes Section, Structures, Mechanisms and Materials Division, Mechanical Department, ESA-ESTEC, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands
³ University Grenoble-Alpes, CNRS, 3SR, 1270 Rue de la Piscine, Gières, France

^* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 1 December 2025

Abstract

Metal-based Directed Energy Deposition, a key variation of additive manufacturing, has emerged as a highly promising technology for space applications. Its ability to function e↵ectively in microgravity, along with unrestricted object size and relatively fast production times, makes it particularly attractive for this sector. However, the technology faces significant challenges, primarily concerning low dimensional precision and recurring defects linked to insufficient control and understanding of powder delivery. Recognizing the need for reliable, cost-efficient, and flexible software solutions, ESA advocates for the integration of Virtual Testing in Process-Structure-Property (PSP) modelling as a viable complement to conventional experimental methods. In response, a novel numerical framework is introduced, leveraging a full coupling of a Discrete Element solver for powder phase modelling and computational fluid dynamics for gas phase modelling to increase the simulation accuracy of powder stream dynamics.