Lattice Boltzmann Method for Simulation of Solutal Interfacial Convection in Gas–Liquid System

Abstract

Two approaches based on the lattice Boltzmann method (LBM), the two-BGK (Bhatnagar, Gross, and Krook)equation LBM and the hybrid LBM−finite-difference method (FDM), were developed for simulations of solutal interfacial convection. Implementations of the gravity/buoyancy and surface tension forces and an interfacial perturbation model, namely, the self-renewal interface model, were proposed for the simulation of interfacial convection, including Rayleigh convection and Marangoni convection, in a gas−liquid mass transfer process. The simulation approaches and model were validated by experimentally measured data via the particle image velocimetry technique for the CO 2 −ethanol system. The performances of the two simulation methods presented in this paper are discussed.

Spatial Scale Effects on Rayleigh Convection and Interfacial Mass Transfer Characteristics in CO2 Absorption

“…A hybrid LBM-FDM [37] was adopted to simulate the Rayleigh convection in CO 2 absorption. In this method, the governing equation of the velocity field is solved by the LBM, and the concentration field is solved by the FDM.…”

“…In this method, the governing equation of the velocity field is solved by the LBM, and the concentration field is solved by the FDM. The detailed hybrid scheme can be found elsewhere [37].…”

“…Following the treatment of Chen et al [37], an appropriate discretization of space and time, i.e., 10 -4 m for lattice grid spacing and 10 -3 s for time step, is adopted to obtain accurate simulation results at a relative moderate level of computation expense.…”

“…The model parameters were identified by comparison of the simulated critical onset time of Rayleigh convection with the experimental and theoretical values in literature. Chen et al [37] described a hybrid LatticeBoltzmann/finite-difference method (LBM-FDM) to perform numerical simulation of solutal interfacial convections in a gasliquid system. According to the experimental validation via PIV measurement, the hybrid scheme was successful in reproducing the velocity distribution of interfacial convection in the absorption of the CO 2 -ethanol system.…”

Modeling with statistical hydrodynamic quantities of mass transfer across gas–liquid interface with Rayleigh convection

“…Fu et al [25] proposed the random disturbance model to mimic actual interfacial disturbance, which is necessary for the onset of Rayleigh convection. Furthermore, Chen et al [26] developed a hybrid Lattice-Boltzmann/finite-difference method (LBM-FDM) to simulate the concentration gradient-induced interfacial convection in gas-liquid systems. The simulation results, which were confirmed by the PIV experiments, reproduced the meso-scale flow behaviors and mass transfer characteristics.…”