Permeability (earth sciences)

About: Permeability (earth sciences) is a research topic. Over the lifetime, 15424 publications have been published within this topic receiving 288535 citations.

Determination of permeability in fibrous porous media using the lattice Boltzmann method with application to PEM fuel cells

Abstract: The lattice Boltzmann method (LBM) is used to simulate the flow through an idealized proton exchange membrane fuel cell (PEMFC) porous transport layer (PTL) geometry generated using a Monte Carlo method. Using the calculated flow field, Darcy's law is applied and the permeability is calculated. This process is applied in both through- and in-plane directions of the paper as both of these permeability values are important in computational fluid dynamics models of PEMFCs. It is shown that the LBM can be used to determine permeability in a random porous media by solving the flow in the microstructure of the material. The permeability in the through- and in-plane directions is shown to be different and the anisotropic nature of the geometry creates anisotropic permeability. It is also found that fiber arrangement plays a large role in the permeability of the PTL. New correlations are presented for in- and though-plane permeabilities of fibrous porous media with (0.6

Estimation of Pressure-Dependent Diffusive Permeability of Coal Using Methane Diffusion Coefficient: Laboratory Measurements and Modeling

Abstract: Gas diffusion in coal is critical for the prediction of coalbed methane (CBM) production, especially for the late-stage CBM reservoir when both gas pressure and permeability are relative low. Using only Darcy permeability to evaluate the quality of gas transport might not be effective. Diffusive flow can be the dominant flow at low reservoir pressures. In this work, the methane diffusion coefficient was measured for pulverized San Juan sub-bituminous and Pittsburgh bituminous coal samples using the classic unipore model and particle method. The diffusion coefficient results showed a negative correlation with pressure, as reported previously. The significance of diffusion flow is strongly related to the rate of the methane ad-/desorption process, more severely in the low pressure range [<2 MPa (280 psi)]. The measured diffusion coefficient can be converted to the equivalent permeability. This equivalent permeability, termed diffusive permeability, can be considered as the contribution of diffusion flow, in...