Precession-driven dynamos in ellipsoidal planets

椭球行星中进动驱动的发电机

• 批准号: 169802462
• 负责人: Professor Dr. Ulrich Hansen
• 金额: --
• 依托单位: Institut für Geophysik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/169802462?language=en
• 关键词: Precession; driven; dynamos; ellipsoidal; planets

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.

到目前为止，数值模拟大多假设产生动力过程的流动是由浮力驱动的。但是，正如布拉德在1949年首次提出的那样，岁差也可以驱动发电机。我们将利用有限体积程序研究岁差驱动行星发电机的性质。在行星中，由进动体的地形引起的压差驱动进动流比由与壁的粘性耦合驱动进动流有效得多。因此，我们将修改现有的程序，这是一个有限体积程序的球壳，使磁流体动力学方程在椭球壳求解。我们将研究岁差驱动发电机的磁场特征，并将其与行星磁场进行比较。