The scope of the present thesis is the development of a Computational Fluid Dynamicsmodel to describe the multiphase flow inside a structured packing absorber for postcombustioncarbon capture. The work focuses mainly on two flow characteristics: theinterface tracking and the reactive mass transfer between the gas and the liquid. The interfacetracking brings the possibility of studying the liquid maldistribution phenomenon,which strongly affects the mass transfer performance. The development of a user-definedfunction to account for the reactive mass transfer between phases constitutes the secondmajor concept considered in this thesis.Numerical models found in the literature are divided into three scales due to the currentcomputational capacity: small-, meso- and large-scale. Small-scale has usually dealtwith interface tracking in 2D computational domains. Meso-scale has usually been consideredto assess the dry pressure drop performance of the packing (considering only thegas phase). Large-scale studies the liquid distribution over the whole column assumingthat the structured packing behaves as a porous medium.This thesis focuses on small- and meso-scale. The novelty of this work lies in expandingthe capabilities of the aforementioned scales. At small-scale, the interfacial trackingis implemented in a 3D domain, instead of 2D. The user-defined function that describesthe reactive mass transfer of CO2 into the aqueous MEA solution is also included to assessthe influence of the liquid maldistribution on the mass transfer performance. At themeso-scale, the Volume of Fluid method for interface tracking is included (instead of onlythe gas phase) to describe flow characteristics such as the liquid hold-up, the interfacialarea and the mass transfer.At the theoretical level, this model presents the particularity of including both a massand a momentum source term in the conservation equations. A comprehensive mathematicaldevelopment shows the influence of the mass source terms on the momentumequation.
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