FLiP: FLuids and Plasmas

This is the official X account of the Fluids and Plasma group at @Fisica_UBA @Exactas_UBA. We share our latest research, publications, and activities. For more details, check our website (linked in bio). Stay tuned for updates!

The key result is that streak waviness scales quadratically with the amplitude once rolls are strong enough. A direct nonlinear link that closes the self-sustaining cycle. Link to the article: journals.aps.org/prfluids/abstr… Link to the arXiv: arxiv.org/abs/2508.03885

For large enough perturbations, the dynamics become much faster and fully nonlinear. At sufficiently large Reynolds and perturbation amplitude, the flow reaches a turbulent steady state; otherwise, it relaminarizes.

New article by @ManuelEtchevest, @DmitrukPablo with Karmakar, Semin, Godoy-Diana and Wesfreid studies the interaction between coherent structures in turbulent couette-poiseuille flow.

Link to the article: journals.aps.org/prfluids/abstr… Link to the arXiv: arxiv.org/abs/2602.08960

These results show that turbulence organizes into two layers of dynamics: large scales set the number of unstable directions and small scales add nonlinear complexity without new instabilities. Moreover, degrees of freedom scale with the forcing scale, not the number of modes.

How many degrees of freedom does turbulence truly have? @melivinograd, @joaquin_cullen, @patriciocdl show that 2D Kolmogorov flow undergoes two sharp transitions. Sweeping across Reynolds number and forcing scale wavenumber, both transitions collapse at the same forcing Reynolds.

Bottom line: it is a practical way to access helicity experimentally, without velocity gradients. Link to the article: journals.aps.org/prfluids/abstr… Link to the arXiv: arxiv.org/abs/2601.08569

The topological features of the flow are imprinted on particle trajectories. Via the local crossing density it is possible to resolve the chiral spatial structure, voxel by voxel, straight from lagrangian data.

New article published as editor's suggestion i'm @PhysRevFluids by @ManuelNoseda, @esp_bernardo, @MininniPablo and @PabloCobelli!

This implies that, in order to model volcanic plumes and related hazards, humidity–turbulence–particle coupling is needed. Dry turbulence assumptions miss key physics. Link to the article: nature.com/articles/s4159…

The authors combine simulations and observational analysis to show that particle dynamics are tightly coupled to turbulent fluctuations, not just mean flow properties.

🌋 @ZFlorenciaN, @MininniPablo with Ravichandran, Cimarelli and Ichihara published a study of turbulence and particle dynamics in volcanic clouds, focusing on how humidity changes the flow physics and particle behavior in these highly transient environments. 🗻

🌊 On friday, Ignacio defended his Master’s thesis on experimental wave turbulence and is now starting his PhD, all under @PabloCobelli's supervision. Congratulations!

Our group @flipdfuba at @Fisica_UBA, and the atmospheric turbulence group at @SMN_Argentina had a wonderful meeting this week during the visit of @EberhardBodens1. Thanks for the visit!

Link to the article: doi.org/10.1017/jfm.20… Link to the arXiv: arxiv.org/abs/2512.05855

The work also analyzes the thermodynamics of particle trajectories. Entropy production along trajectories satisfies the Integral Fluctuation Theorem and, under certain conditions, the Detailed Fluctuation Theorem, linking stochastic thermodynamics with turbulent transport.

New paper by @esp_bernardo, @MininniPablo, Joachim Peinke, @ManuelNoseda, @PabloCobelli and Martin Obligado. The work studies inertial particles in turbulence using both DNS and laboratory experiments of turbulent swirling flow under a Fokker-Planck approach to turbulence.