Multiphase flows with surface tension

Bubbles and drops are critical components of important industrial applications such as boiling and condensation, bubble column reactors, electrochemical cells and physical systems involving air entrainment in plunging jets and liquid jet atomization.

Effects of surface tension are important for these applications and present a challenge for numerical simulations.
We develop models, numerical methods and software for simulation of such flows.
People: Petr Karnakov, Sergey Litvinov, Petros Koumoutsakos

Membrane-less electrochemical reactors

In traditional electrochemical reactors, the products forming on the electrodes are separated by a membrane. Flow based electrochemical instead rely on hydrodynamic mechanisms to keep the products separated. One of these mechanisms is the Segre-Silberberg effect of lateral migration of a particle in a channel flow: the particle finds a stable equilibrium position near the wall. With proper flow conditions, the gaseous products in the form of bubbles can be kept separated.

Removing the membrane can reduce the ionic resistance of the reactor leading to an increase in power conversion efficiency. This, however, requires strong understanding of the underlying processes. Combining numerical modelling with experiments done by our collaborators, we aim to fully investigate the operation of flow-based electrochemical reactors and provide tools for their optimal design.

Publications

2020

  • P. Karnakov, S. Litvinov, and P. Koumoutsakos, “A hybrid particle volume-of-fluid method for curvature estimation in multiphase flows," Int. J. Multiphas. Flow, vol. 125, p. 103209, 2020.
    [BibTeX] [PDF] [DOI]
    @article{karnakov2020a,
    author = {Petr Karnakov and Sergey Litvinov and Petros Koumoutsakos},
    doi = {10.1016/j.ijmultiphaseflow.2020.103209},
    journal = {{Int. J. Multiphas. Flow}},
    month = {apr},
    pages = {103209},
    publisher = {Elsevier {BV}},
    title = {A hybrid particle volume-of-fluid method for curvature estimation in multiphase flows},
    url = {http://www.cse-lab.ethz.ch/wp-content/papercite-data/pdf/karnakov2020a.pdf},
    volume = {125},
    year = {2020}
    }

  • Z. Y. Wan, P. Karnakov, P. Koumoutsakos, and T. P. Sapsis, “Bubbles in turbulent flows: data-driven, kinematic models with history terms," Int. J. Multiphas. Flow, vol. 129, p. 103286, 2020.
    [BibTeX] [PDF] [DOI]
    @article{wan2020a,
    author = {Zhong Yi Wan and Petr Karnakov and Petros Koumoutsakos and Themistoklis P. Sapsis},
    doi = {10.1016/j.ijmultiphaseflow.2020.103286},
    journal = {{Int. J. Multiphas. Flow}},
    month = {aug},
    pages = {103286},
    publisher = {Elsevier {BV}},
    title = {Bubbles in turbulent flows: Data-driven, kinematic models with history terms},
    url = {http://www.cse-lab.ethz.ch/wp-content/papercite-data/pdf/wan2020a.pdf},
    volume = {129},
    year = {2020}
    }

2019

  • S. M. H. Hashemi, P. Karnakov, P. Hadikhani, E. Chinello, S. Litvinov, C. Moser, P. Koumoutsakos, and D. Psaltis, “A versatile and membrane-less electrochemical reactor for the electrolysis of water and brine," Energ. Environ. Sci., 2019.
    [BibTeX] [PDF] [DOI]
    @article{hashemi2019a,
    author = {Seyyed Mohammad Hosseini Hashemi and Petr Karnakov and Pooria Hadikhani and Enrico Chinello and Sergey Litvinov and Christophe Moser and Petros Koumoutsakos and Demetri Psaltis},
    doi = {10.1039/c9ee00219g},
    journal = {{Energ. Environ. Sci.}},
    publisher = {Royal Society of Chemistry ({RSC})},
    title = {A versatile and membrane-less electrochemical reactor for the electrolysis of water and brine},
    url = {http://www.cse-lab.ethz.ch/wp-content/papercite-data/pdf/hashemi2019a.pdf},
    year = {2019}
    }

  • P. Karnakov, F. Wermelinger, M. Chatzimanolakis, S. Litvinov, and P. Koumoutsakos, “A high performance computing framework for multiphase, turbulent flows on structured grids," in Proceedings of the platform for advanced scientific computing conference – PASC ’19, 2019.
    [BibTeX] [PDF] [DOI]
    @InProceedings{karnakov2019a,
    author = {Petr Karnakov and Fabian Wermelinger and Michail Chatzimanolakis and Sergey Litvinov and Petros Koumoutsakos},
    booktitle = {Proceedings of the Platform for Advanced Scientific Computing Conference - {PASC} {\textquotesingle}19},
    title = {A High Performance Computing Framework for Multiphase, Turbulent Flows on Structured Grids},
    year = {2019},
    publisher = {{ACM} Press},
    doi = {10.1145/3324989.3325727},
    url = {http://www.cse-lab.ethz.ch/wp-content/papercite-data/pdf/karnakov2019a.pdf},
    }

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