Measurement of tortuosity of porous Cu using a diffusion diaphragm cell

Open-cell porous metals have many potential applications, such as heat exchangers and flow batteries, due to good permeability for fluid flow. Porous metals manufactured by space holder methods have controllable porous structure, but the fluid pathways and channels are tortuous. The tortuosity can directly influence the fluid permeability and turbulence, which in turn affect the performance of the porous metal. This paper measured the tortuosity of porous Cu, manufactured by Lost Carbonate Sintering (LCS), directly by a diffusion method using a diaphragm cell. The tortuosity of the samples with pore sizes 250-1500 µm and porosities 0.56-0.84 was in the range of 1.33-1.78. It decreased with porosity and increased with pore size. The measured values were comparable to those reported in literature, obtained by the acoustic absorption method.