Completed
Interior of the Earth
Class Central Classrooms beta
YouTube videos curated by Class Central.
Classroom Contents
Planetary Dynamos
Automatically move to the next video in the Classroom when playback concludes
- 1 Planetary Dynamos
- 2 Planetary Magnetospheres
- 3 Planetary Auroras are one indication of a magnetic dipole field
- 4 Internal Dynamo in a Liquid Core Generates the Main Planetary Magnetic Field
- 5 Planetary Data
- 6 (Some) Geodynamo Researchers
- 7 Interior of the Earth
- 8 The Earth’s Inner Core
- 9 Geological Record: Geomagnetic Excursions
- 10 Basic Equations Mathematical model based on the magnetohydrodynamic (MHD) equations with buoyancy → the 'Boussinesq approximation : compositional variation is not included because of strong mixing.
- 11 Numerical Modeling Solve nonlinear partial differential equations (PDEs) on computer. Various methods: finite difference, finite volume,.... For regular geometries, we can choose a spectral method
- 12 Geodynamo Parameters
- 13 Magnetic Fields Turbulent relaxation of ideal magneto-fluid
- 14 Spectral Method Model
- 15 Spherical Harmonics
- 16 Function Expansions for Spherical Shells
- 17 Coefficients = Dynamical Variables
- 18 A Dynamical System The spectral method tums a few PDEs into many coupled ODES
- 19 Statistics of Ideal MHD Turbulence
- 20 Probability Density Function (PDF) The invariants for ideal MHD are
- 21 Expectation Values
- 22 Cross Helicity, HC He is essentially the cross correlation between velocity and magnetic field in the liquid core.
- 23 Expected Dipole Angle 0 vs Cross Helicity Hc The dipole angle can be calculated using the statistical theory, with maximum , i, m = 100 Large-scale numerical simulations of ideal, rotating MHD turbul…
- 24 Summary: The Ideal MHD Geodynamo
- 25 Conclusion
