The JHU Turbulence Database Cluster

Visualization with Matlab

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Overview

• Recap of already presented stuff• New premade scripts• A few demos

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Recap #1

• Easy to use scripts: input boxes• Caching requests locally• Modified SOAP functions to speed up

request construction and parsing

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Recap #2

• 2D vector maps • 3D iso vorticity

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New vorticity scalar fields

• Q-criterion (second invariant of velocity gradient tensor)

• Lambda-2 criterion (negative second Eigenvalue of S2+Ω2)

• Complex Eigenvalues of velocity gradient

• Pressure hessian trace

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Energy spectra

• Randomly chosen lines• Fast Fourier Transform of inline

velocity component• Computation of scaled energy

spectra• Comparison with inertial sub range

line

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PDFs

• Randomly positioned cube of points: 323 points evenly distributed on 2563

• PDF of velocity components and pressure in this block with Matlab hist() function

• Log(PDF) of velocity gradient components (transverse and longitudinal)

• Nondimensionalized x-axis• Adapted bin width in logarithmic PDF

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PDFs of velocity increments

• Velocity increment:• Longitudinal: , transverse:

• Distribution of r:

• Randomly positioned and oriented block of 32x128x512 points, queried by 323 points

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