An advanced CFD model with porous based immersed boundary method for adsorption kinematics at a particle’s scale

A new Computational Fluid Dynamics (CFD) model has been developed and validated for multi-species fluid flow past an adsorbing particle (diameter d p ≥ 1 μ m ). For the first time, this model can predict the local adsorption kinematics at the scale of a pellet thanks to a new direct forcing porous based immersed boundary method (PB-IBM) developed within the open-source CFD platform OpenFOAM . The new PB-IBM is validated for different 3D flows past a porous sphere at different Reynolds numbers in comparisons with PIV (Particles Image Velocimetry) and LBM (Lattice Boltzmann Method) data from the literature. The new model is also validated for the coupled flow, adsorption kinematics and heat transfer front evolution inside an adsorbing cylindrical fixed bed packed with about 5000 adsorbing zeolite-13X beads to capture CO 2 from a feed of 50%CO 2 /50%He mixture at atmospheric pressure. Finally, to highlight the advanced capabilities of the present new model at the particle’s scale, the case of an irregular shaped adsorbing particle is investigated and compared to the case of a regular particle (sphere) for CO 2 adsorption on zeolite-13X with 50%CO 2 /50%He feed at R e p ≈ 1 . 75 , atmospheric pressure and T = 22 ° C . The model is able to capture the transient behavior of the different important local phenomena inside the particle such as the local pressure, temperature and the local adsorbed quantity. The irregular shaped particle outer-performed the spherical particle where its adsorption capacity is higher over all time steps with a maximum increase of about 34%. The model is thus very promising to optimize and design future particulate matter matrices as innovative designs of adsorbing materials for different adsorption/desorption applications.