Multiscale properties of turbulence in bubble-laden flows

Bubble-induced turbulence (BIT) plays an important role in mixing, transport and collision of small particles in many natural and industrial applications. We investigate the properties of bubble-laden turbulent flows at different scales, focusing on the flow kinetic energy, anisotropy, energy transfer and extreme events. The experiments employed either 2D PSV or 3D LPT measurements to measure the flow in a column generated by a homogeneous bubble swarm rising in water. Furthermore, we also explore the Lagrangian description of BIT, e.g. the relative particle pair dispersion, based on the relative separation of tracer particles. The aim is both to develop a fundamental understanding and characterization of the multiscale physics of these flows as well develop new models to predict their behavior.

Publications

• Ma, T., Hessenkemper, H., Lucas, D. & Bragg, D. A.
  Effects of surfactants on bubble-induced turbulence.  J. Fluid Mech. 970 (2023), A13

• Ma, T., Hessenkemper, H., Lucas, D. & Bragg, D. A.
  An experimental study on the multiscale properties of turbulence in bubble-laden flows.  J. Fluid Mech. 936 (2022), A42

• Ma, T., Ott, B., Fröhlich, J. & Bragg, D. A.
  Scale-dependent anisotropy, energy transfer and intermittency in bubble-laden turbulent flows.  J. Fluid Mech. 927 (2021), A16.