A New Formulation for Prediction of Permeability of Nano Porous Structures using Lattice Botzmann Method

Abstract

The standard lattice Boltzmann equation, LBE, is inadequate for simulating gas flows in nano scale flows with Knudsen numbers higher than 0.1. In the present study, rarefied gas flow in nano porous structures is simulated using the modified Lattice Boltzmann Method, LBM, which is able to cover wide range of flow regimes. The present study, reports the effects of the Knudsen number and porosity on the flow rate and permeability in slip and transitional flow regimes. For the first time, the Knudsen's minimum effect in micro/nano porous was observed. A new correlation between the permeability, the porosity and the Knudsen number is then proposed which is able to predict the permeability of in-line and staggered nano porous structures in slip and transitional regimes.

Hydrothermal analysis of water-Al2O3 nanofluid flow through a sudden expansion channel with intermediate step

“…Generally, the porous media is used in the channels to increase the rate of HT. Flow through a sudden expansion channel is a well-known phenomenon [Mostafavi et al (2017)]. Many authors [Mostafavi et al (2017); Menouer et al (2019)], experimentally and numerically, have shown that the increase in Re causes the existence of two or more flow separation zones at the lower and upper corner walls, which causes a substantial heat loss [Galuppo et al (2017)].…”

“…Flow through a sudden expansion channel is a well-known phenomenon [Mostafavi et al (2017)]. Many authors [Mostafavi et al (2017); Menouer et al (2019)], experimentally and numerically, have shown that the increase in Re causes the existence of two or more flow separation zones at the lower and upper corner walls, which causes a substantial heat loss [Galuppo et al (2017)]. Hilo et al (2020) studied different properties of the hydrothermal phenomena of flow over a suddenly expanded channel.…”

An Investigation of Transition Flow in Porous Media by Event Driven Molecular Dynamics Simulation

“…All permeability models given so far apply to continuum flow regime. Mostafavi et al (2017) proposed relation given in eq. ( 9), which also depends on Kn, for the porosity calculation of the porous structure formed by in-line arrangement of square particles.…”