Experimental Determination of Packed-Bed Tortuosity from Centrifugally Induced Gas-Pressure Profiles

A novel method for quantifying tortuosity by analyzing the pressure distribution of gas within a rotating porous bed is presented. The method utilizes a custom-designed disc-shaped cell packed with activated carbon particles and subjected to a high-speed rotation of 5000 rpm under an equilibrium initial pressure of 5045 mbar CO2. The theory related to this method is outlined. From the radial pressure distribution, the apparent tortuosity is estimated to be ~2.3. This value is independently validated using an extracted apparent diffusion coefficient of Dapp = (9.7 ± 0.3) × 10−7 m2/s and a corresponding tortuosity of τapp = 2.2 ± 0.8. The findings establish a new route for probing the interplay between pore geometry, gas transport, and adsorption phenomena under centrifugal forces.