Performance Assessment of a Three-Dimensional Printed Porous Media Produced by Selective Laser Melting Technology for the Optimization of Loop Heat Pipe Wicks

Abstract

The primary wick in a loop heat pipe device is a key component that is central to the operation of the device. Both high permeability and capillary pumping capacity, two properties highly dependent on wick structure, are strongly desirable for a satisfactory thermal performance. In this paper, selective laser melting (SLM), a three-dimensional (3D) printing technology, is used to create a primary wick for an 80 W heat transfer application. The permeability and capillarity values of this wick, experimentally measured, are compared with those built with the most widely used technologies nowadays, such as powder sintering and meshes. In this study, the SLM scaffold is shown to satisfy the minimum values required by the application in terms of capillarity and permeability: 0.031 mm/s and 4 × 10−12 m2, respectively. Our comparative study revealed that the wick produced with the SLM technology presented higher values of permeability, by two orders of magnitude, and slightly higher capillary figures than those corresponding to powder sintering for such application. However, it had capillary values well below those of a stainless-steel mesh. The hydraulic behavior of the SLM wick was better than that of the sintered copper powder, because it not only met the above-mentioned specifications, but it also improved its performance.

PoroFluidics: Deterministic fluid control in porous microfluidics

“…Owing to its porous structure, multiple streams of fluids can be simultaneously achieved in a single volume, demonstrating excellent potential for the parallelization of multiple fluid channels and high interfacial areas that facilitate mixing/reaction processes 9 . Although efforts have been made to advance the fundamental understanding of the fluid transport processes in the micro-architected materials with lattice structures 4,[10][11][12] , most investigations have focused on single-phase flow. A recent notable work by Dudukovic et al 9 demonstrated the precise manipulation of multi-phase flow in the open lattice structures, where capillary-driven fluid flow along preferential pathways is achieved.…”

Performance characterisation and printing parameter modelling of selective laser melting printed capillary wicks

“…They found that the printed capillary wick cloud enhanced the heat transfer performance of the heat pipe with an increase in the capillary size according to h ( t )– t (1/3) in the intermediate stage, although gravity affected the rise of liquid in the capillary wick. Esarte et al (2019) designed and 3D-printed a frame-type 316 stainless steel capillary wick porous structure for an LHP with a heat transfer requirement of 80 W and experimentally tested its permeability and capillary rise height. The results showed that the permeability of an SLM capillary wick is two orders of magnitude greater than that of a powder-sintered capillary wick.…”