We adopted LBGK model of heat-mass coupling in lattice Boltzmann method to simulate double diffusion mixed convection, fluid-solid conjugate heat transfer and adsorption process in an enclosure filled with spherical activated carbon with real physical parameters at pore scale. D2Q9 model was used to describe velocity and temperature fields, and D2Q5 for concentration fields, respectively. Impact of activated carbon particle size, porosity and particle arrangement on entire dynamic adsorption performance was investigated. It shows that with increased activated carbon particle size the time to approach steady is increased and the adsorption rate is moderated at porosity 0.85. At particle diameter 0.43 mm, the adsorption rate is the highest and the adsorption time is the shortest. Transient adsorption capability and time consumption to equilibrium were independent of filling rate. Compared with those of line and dislocation arrangement of activated carbon particles, transient adsorption capability of random and non-adherent arrangement is better.

We adopted lattice Boltzmann method to simulate double diffusion mixed convection, fluid-solid conjugate heat transfer and adsorption process in a lid-driven composite enclosure filled with homogeneous medium at pore scale. Influences of buoyancy ratio Br (-100 ≤ Br ≤ 100) and adsorption rate constant k₁ (0.001 ≤ k₁ ≤ 0.005) on characteristics of heat and mass transfer were compared at porosity ε=0.79, Prandtl number Pr=0.7, Grashof number Gr=10⁴ and Lewis number Le=1.0. Streamlines, isotherms, isoconcentrations, adsorption capacity (C_S), average Nusselt number Nu_av and Sherwood number Sh_av of the left heated wall under different parameters were discussed in detail. It shows that Br affects adsorption by changing concentration distribution around medium in flow field; Increasing k₁ improves significantly adsorption efficiency and adsorption capacity.