Turbulence modulation in buoyancy-driven bubbly flows
arXiv:2105.04812 · doi:10.1017/jfm.2021.942
Abstract
We present a Direct Numerical Simulation (DNS) study of buoyancy-driven bubbly flows in the presence of large scale driving that generates turbulence. On increasing the turbulence intensity: (a) the bubble trajectories become more curved, and (b) the average rise velocity of the bubbles decreases. We find that the energy spectrum of the flow shows a pseudo-turbulence scaling for length scales smaller than the bubble diameter and a Kolmogorov scaling for scales larger than the bubble diameter. We conduct a scale-by-scale energy budget analysis to understand the scaling behaviour observed in the spectrum. Although our bubbles are weakly buoyant, the statistical properties of our DNS are consistent with the experiments that investigate turbulence modulation by air bubbles in water.
References in corpus (6)
- Experimental investigation of the turbulence induced by a bubble swarm rising within an incident turbulence
- Rheology of suspensions of viscoelastic spheres: deformability as an effective volume fraction
- Liquid velocity fluctuations and energy spectra in three-dimensional buoyancy driven bubbly flows
- Global and local statistics in turbulent emulsions
- Scale-dependent anisotropy, energy transfer and intermittency in bubble-laden turbulent flows
- On the local energy flux of turbulent flows