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Numerical Methods for Investigating Mixing

Numerical Methods for Investigating Mixing

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Field approach

Tracer Method

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2nd  : Interpolate velocities within gridcells:

3rd Integrate tracers in Time:

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Active tracers

3rd : Marker chain method:

Comparison between methods:

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Different numerical methods - Conclusion

Mixing in Convection

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 Mixing in 2D time-periodic flows:

 Aref (1984) Blinking vortex flow:

- even simple 2D time-periodic flows can exhibit lagrangian chaos

2D time-dependent flows

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Experiments & Kinematic approach (Solomon&Gollub) :

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Higher Rayleigh number:

3D Convective flows

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Multiple tracers. ..

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Hexagonal patterns:

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Spherical geometry:

Comparison with ABC flows:

defined by :

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Conlucsion 3D statonary convection

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Conclusion Stationary convection:

Time-dependent convection:

Movie:

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High Raylaeigh numbers:

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Conclusion time-dep. Convection

More realistic parameters:
- varable viscosity

 The influence of plate motion on the                           mixing process

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Conclusion time-dep. convection with variable viscosity