InterPore2026

Hierarchical porous media with well-defined microstructures for capillary-driven evaporation and their application in passive heat transfer devices.

19 May 2026, 09:50

1h 30m

Poster Presentation (MS16) Complex fluid and Fluid-Solid-Thermal coupled process in porous media: Modeling and Experiment Poster

Speaker

Jiaxi Du (Harbin Institute of Technology (Shenzhen))

Description

The simultaneous increase in electronic device integration density and thermal design power (TDP) in recent years has created significant challenges for thermal management. This has made flat and even ultra-thin passive phase-change heat transfer devices suitable for confined spaces a major research focus in this field. Representative ultra-thin vapor chambers and flat heat pipes now have thicknesses reduced to 300 micrometers or less. Conventional porous media wicking structures, such as those made from sintered powder, screen mesh, or metallic foam, struggle to meet the size and performance requirements of next-generation communication devices. The limitations of these materials primarily include inherent difficulties in reducing raw material thickness, an inability to balance the conflicting demands of capillary pressure and flow resistance, and limited enhancement of phase-change heat transfer. To address these issues, this study proposes and successfully fabricates a novel porous media featuring a well-defined microstructure. Microscopically, this structure functions as a hybrid system combining microchannels and micropore arrays. Smooth, straight microchannels minimize flow resistance, while the micropore structures enhance thin-film evaporation and provide high capillary pressure. The capillary performance and phase-change heat transfer enhancement of this novel wick were experimentally validated through independent capillary rise tests and capillary-driven evaporation tests under adverse gravity conditions. Furthermore, a multiscale model coupling unit cell-level heat transfer and percolation characteristics with chip-scale macroscopic heat transfer was developed to predict its performance in ultra-thin passive heat transfer devices. Ultimately, this novel porous media was integrated into an ultra-thin flat heat pipe with a thickness of only 220 micrometers, achieving highly effective heat transfer with an equivalent thermal conductivity of up to 17,000 W/m·K.