Yield Stress Fluid Method to Measure the Pore Size Distribution of a Porous Medium

In this paper a new method is presented in order to determine the pore size distribution in a porous media. This original technique uses the non Newtonian yield-pseudo-plastic rheological properties of some fluid flowing through the porous sample. In a first approximation, the very well-known and simple Carman-Kozeny model for porous media is considered. However, despite the use of such a huge simplification, the analysis of the geometry still remains an interesting problem. Then, the pore size distribution can be obtained from the measurement of the total flow rate as a function of the imposed pressure gradient. Using some yield-pseudo-plastic fluid, the mathematical processing of experimental data should give an insight of the pore-size distribution of the studied porous material. The present technique was successfully tested analytically and numerically for classical pore size distributions such as the Gaussian and the bimodal distributions using Bingham or Casson fluids (the technique was also successfully extended to Herschel-Bulkley fluids but the results are not presented in this paper). The simplicity and the cheapness of this method are also its assets.