DNS of Mass Transfer in Bi-dispersed Bubble Swarms

This work presents Direct Numerical Simulation of mass transfer in a bi-dispersed bubble swarm at high Reynolds number, by using a multiple marker level-set method. Transport equations are discretized by the finite-volume method on 3D collocated unstructured meshes. Interface capturing is performed by the unstructured conservative level-set method, whereas the multiple marker approach avoids the so-called numerical coalescence of bubbles. Pressure-velocity coupling is solved by the classical fractional-step projection method. Diffusive terms are discretized by a central difference scheme. Convective term of momentum equation, level-set equations, and mass transfer equation, are discretized by unstructured flux-limiters schemes. This approach improves the numerical stability of the unstructured multiphase solver in bubbly flows with high Reynolds number and high-density ratio. Finally, this numerical model is applied to research the effect of bubble-bubble interactions on the mass transfer in a bi-dispersed bubble swarm.Nestor Balcázar, as a Professor Serra-Hnter (UPC-LE8027), acknowledges the Catalan Government for the financial support through this programme. The authors acknowledges the financial support of the Ministerio de Economía y Competitividad, Secretaría de Estado de Investigación, Desarrollo e Innovación (MINECO), Spain (PID2020-115837RB-100). Simulations were executed using computing time granted by the RES (IM-2021-3-0013, IM-2021-2-0020, IM-2021-1-0013, IM-2020-2-0002, IM-2019-3-0015) on the supercomputer MareNostrum IV based in Barcelona, Spain.Peer ReviewedPostprint (published version