Investigating Fluidisation of Powder in the Supply Bins of Polymer Laser Sintering Machines Using Foundational 2D Numerical Modelling

Fredrick  Mwania; Maina  Maringa; Jacobus van der  Walt

doi:10.6000/1929-5995.2026.15.04

Authors

Fredrick Mwania Department of Mechanical and Mechatronic Engineering Central University of Technology, 20 President Brand Street, Bloemfontein, South Africa
Maina Maringa Department of Mechanical Engineering, Murang’a University of Technology, P. O. Box 75-10200 Murang’a, Kenya
Jacobus van der Walt Department of Mechanical and Mechatronic Engineering Central University of Technology, 20 President Brand Street, Bloemfontein, South Africa

DOI:

https://doi.org/10.6000/1929-5995.2026.15.04

Keywords:

Fluidisation-flowrate, fluidisation-time, bulk density, particle size, powder bed height

Abstract

Fluidisation is a critical process in polymer laser sintering, but limited studies have been conducted in this area. In this regard, two-dimensional numerical models were used, in this study, to establish a suitable flowrate and period of fluidization for a polypropylene powder material used as a feedstock in polymer laser sintering. The study also investigated the impact of different spreading parameters and properties of material such as, bulk-density, particle-size, and fluidised bed height, on the fluidisation behaviour of powder in the supply bins of EOS P380, P385, and P396 machines. A computational fluid dynamic (CFD) software, Fluent, was identified and applied to investigate the fluidisation behaviour of a polypropylene material. The results arising from the numerical modelling revealed that the suitable fluidisation-flowrate for the material considered is 20 liters/min and the period lies between one and three seconds. It was also established that it might be difficult to fluidise polymeric materials with a density equal to or greater than 1500 kg/m³, particle sizes equal to or greater than 90 µm, and for bed heights below 0.10 m.

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