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Updated: Aug 5, 2026
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Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
Two-dimensional turbulent condensates without bottom drag
Adrian van Kan1, Alexandros Alexakis2, Edgar Knobloch1
1Department of Physics, University of California Berkeley , Berkeley, CA, USA.
Summary
Statistical theory applies to driven dissipative dynamics near the onset of 2D turbulence condensates. Beyond this, deviations occur, with energy dissipation concentrated in large-scale condensates.
Area of Science:
- Fluid dynamics
- Statistical physics
- Turbulence theory
Background:
- The applicability of equilibrium statistical theory to driven dissipative systems is a key unresolved question.
- Understanding large-scale condensates in 2D turbulence is crucial for fluid dynamics and statistical physics.
Purpose of the Study:
- To investigate the steady state of large-scale condensates in 2D turbulence using direct numerical simulations.
- To determine the conditions under which equilibrium statistical theory applies to driven dissipative 2D turbulence.
Main Methods:
- Extensive direct numerical simulations (DNS) of the incompressible 2D Navier-Stokes equation.
- Analysis of energy spectra and vorticity profiles at various finite Reynolds numbers (Re).
Main Results:
- Large-scale condensates emerge above a critical Reynolds number (Rec ≈ 4.19).
- Near onset, energy spectra follow Kraichnan's absolute equilibrium form; at higher Re, spectra deviate, showing a -5 power-law range.
- Energy dissipation concentrates within large-scale condensates at higher Re.
Conclusions:
- 2D turbulent flows exhibit behavior close to equilibrium dynamics in weakly turbulent regimes.
- In strong condensate regimes (Re >> 1), large scales deviate significantly from equilibrium dynamics.
- Findings provide insights into turbulent condensation in finite 2D flows, reconciling theoretical predictions with simulation data.
Keywords:
direct numerical simulationsdriven dissipative dynamicslarge-scale condensatequasi-linear theorystatistical equilibriumtwo-dimensional turbulenceviscous saturationMore Related Videos
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