GPU-accelerated transient lattice Boltzmann simulation of bubble column reactors

Abstract

Design parameters for Bubble Column Reactors such as backmixing and light/dark cycles of microalgae cells are pertinent to transient flow dynamics and mesoscale coherent structures. Transient simulation is therefore of practical significance. Traditional CFD solvers are generally implemented on multi-core CPU workstations, which is time-consuming and difficult to meet the requirement of industry applications. We developed a GPU-accelerated transient LBM simulation of gas-liquid flow, achieving 5000 times acceleration in comparison with the CFD simulation. A notable feature of this method, which allows a tunable and smaller dimensionless relaxation time, is the remarkable decrease of required mesh number in LBM simulation by several orders of magnitude. The solver is validated against experimental data, resolving two mechanisms of mesoscale structure, i.e., vortex rotation and radial migration, in the intensification of macromixing. The computation acceleration and resolution of mesoscale structures demonstrate the potential of this approach for fast simulation of industrial applications.