Buoyancy-driven flow through a bed of solid particles produces a new form of Rayleigh-Taylor turbulence
arXiv:1902.01123 · doi:10.1103/PhysRevLett.121.224501
Abstract
Rayleigh--Taylor fluid turbulence through a bed of rigid, finite-size, spheres is investigated by means of high-resolution Direct Numerical Simulations (DNS), fully coupling the fluid and the solid phase via a state-of-the art Immersed Boundary Method (IBM). The porous character of the medium reveals a totally different physics for the mixing process when compared to the well-known phenomenology of classical RT mixing. For sufficiently small porosity, the growth-rate of the mixing layer is linear in time (instead of quadratical) and the velocity fluctuations tend to saturate to a constant value (instead of linearly growing). We propose an effective continuum model to fully explain these results where porosity originated by the finite-size spheres is parameterized by a friction coefficient.
arXiv comment5 pages, 6 figures
References in corpus (9)
- Turbulent channel flow of dense suspensions of neutrally-buoyant spheres
- On the miscible Rayleigh-Taylor instability: two and three dimensions
- Laminar, turbulent and inertial shear-thickening regimes in channel flow of neutrally buoyant particle suspensions
- Rayleigh--Taylor turbulence in two dimensions
- Self-Similarity and Universality in Rayleigh-Taylor, Boussinesq Turbulence
- Polymer heat transport enhancement in thermal convection: the case of Rayleigh-Taylor turbulence
- Statistics of mixing in three-dimensional Rayleigh--Taylor turbulence at low Atwood number and Prandtl number one
- Nonlinear diffusion model for Rayleigh-Taylor mixing
- Rotating Rayleigh-Taylor turbulence
Cited by in corpus (3)
- From Rayleigh-Bénard convection to porous-media convection: how porosity affects heat transfer and flow structure
- Towards the understanding of convective dissolution in confined porous media: thin bead pack experiments, two-dimensional direct numerical simulations and physical models
- Lagrangian dynamics and heat transfer in porous media convection