Precession-driven dynamos in ellipsoidal planets

到目前为止，数值模拟大多假设产生发电机过程的流动是由浮力驱动的。但正如布拉德在1949年首次提出的那样，进动也可以驱动发电机。我们将用有限体积程序来研究岁差驱动的行星发电机的性质。在行星上，用进动体地形引起的压差来驱动进动流比用与壁面的粘性耦合来驱动进动流要有效得多。因此，我们将对现有的球壳有限体积程序进行修改，求解椭球壳的磁流体动力学方程。我们将研究进动发电机磁场的特征，并将其与行星磁场进行比较。

So far numerical simulations have mostly assumed that the flow generating the dynamo-process is driven by buoyancy forces. But also precession can drive the dynamo, as first suggested by Bullard in 1949. We are going to investigate the properties of precession-driven planetary dynamos by the use of a finite volume code. In the planets it is much more effective to drive a precessional flow by the pressure differences induced by the topography of the precessing body than by viscous coupling to the walls. Therefore we will modify the existing program, which is a finite volume code for spherical shells, so that the magneto-hydrodynamic equations in ellipsoidal shells are solved. We are going to investigate the characteristic features of the magnetic fields of precession driven dynamos and compare them to the planetary magnetic fields.