Aric Videos - EnSight

The Taylor-Green vortex is one of the simplest systems in which to study the generation of small scales and turbulence by 3D vortex stretching:
- Evolution from a simple initial vortex flow provides a dynamical model of decaying turbulence.
- Used as a test of our continuous adaptive mesh refinement code RAGE.

Here we wish to understand the dynamical onset and eventual decay of the turbulence by using EnSight to display many diverse quantities simultaneously:
- Use EnSight to extract a brick of floats containing the 3 velocity components.
- Perform 3D FFT’s on the 3 velocity components with a Fortran routine.
- Take angular averages over direction in k space to form the power spectrum of the kinetic energy vs |k|.
- Convert the power spectrum vs |k| on every timestep to a 1D part.
- Animate everything together on the same image to study the dynamical evolution from the initial coherent vortex flow to fully turbulent Kolmogorov flow that decays away in late time.

Simulation courtesy of F. Grinstein, LANL
1280x1024, 13MB

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