CFD and strength analysis of novel biomimetic lattice structure designed for additive manufacturing and post-processing

• Design of novel lattice structure to address powder removal challenges in polymer powder-based AM processes. • Ventilated 3D lattice structure designed to enable parallel and cross-flow of powder. • CFD simulation can show internal flow channels and overall flow resistance due to the design of various lattice structures. • The powder removal experiment can evaluate the powder flowability in various lattices. • Novel lattice structure's anisotropic behavior proven by FEA and experimental compression tests. The laborious work of post-processing powder removal from lattice structures made by polymer powder-based additive manufacturing (AM) process is still a major challenge and requires in-depth study. Here, a novel 3D honeycomb shaped lattice structure with ventilated holes bio-inspired from polyhedral plant cells has been designed to eliminate powder entrapment in constricted inter-cellular regions of surface-based lattice structure. The ventilation enables cross flow of powder within the lattice structure, resulting in easy and complete removal of entrapped powder. The computational fluid dynamics (CFD) method was used to understand the flow paths in various surface based lattice structures. An experimental setup was also designed to calculate the powder flowability from these lattices. The Finite Element Analysis (FEA) method and compression tests of various lattice structures were done to benchmark the strength of newly designed lattice structure. This innovative lattice structure can be used in biomedical, heat-exchanger, food and drug delivery systems and light-weighting applications.