Direct Numerical Simulation for Flooding Behavior in Counter-current Gas/Liquid Flow Systems for Carbon Capture

Understanding incipient flooding is crucial for industrial systems that involve liquid-gas counter current flow. A biocatalytic textile-based gas-liquid contactor is one application that utilizes immobilized enzymes to accelerate CO₂ capture. A spiral-wound design of such structured packing is assembled by folding cheesecloth fabric over the long edge of a rectangular mesh reinforcement and rolling up the sandwich as a tube. Counter-current flow takes place between an aqueous K₂CO₃ solution and an N₂ and CO₂ gas mixture. Evaluating gas/liquid interactions using two-phase flow capabilities is a challenging problem. Owing to the complex geometry and flow, an investigation of interfacial waves is necessary to understand the local mechanisms initiating the transition to flooding. Identifying counter-current flow limitations (CCFL) are important as these inhibit the interaction of carbon-dioxide with biocatalytic surfaces. Direct numerical simulation (DNS) approach with PHASTA code is utilized to establish predictive metrics for identifying CCFL proposed in the biocatalytic reactor design. Strong influence of instantaneous flow parameters requires local mesh refinement for the resolution of interfaces. Simulations that evaluate the two-phase flow can lead to developing models that predict two-phase flow behavior from global parameters to benefit improved contactor design for efficient CO₂ capture.