Figure 3
From: Scale separated low viscosity dynamos and dissipation within the Earth’s core
Time-averaged energy spectra. (a) Kinetic energy spectra (volume averaged) as a function of spherical harmonic degree l are compared for Case S0 (a dynamo) and Case HYDRO0: we see that the Lorentz force modifies the velocity field at all scales from l = 1 to l~150. (b) Magnetic and kinetic energy spectra as a function of spherical harmonic degree l for Case S4. The Ekman number is 3 × 10−7 and Prm = 0.05. There is scale separation between the large scale magnetic field peaking at l = 1 and the velocity field with maximum energy at l = 9. Note that the magnetic energy, which is ten times larger in total than the kinetic energy, exceeds the latter for all l < 100.
