Publisher: National Agricultural Research Projects

Effects of Brinkman Number On Thermal-Driven Convective Spherical Dynamos

M. I. Ngwueke, T. M. Abbey
KEYWORDS: Magnetic field generation, Thermal-driven convection, Brinkman number, Dynamo action, Fluid outer core


Brinkman number effects on the thermal-driven convective spherical dynamos arestudied analytically. The high temperature of the Earth’s inner core boundary is usually conducted by the viscous, electrically conducting fluid of the outer core to the core mantle boundary as the Earth cools. The problem considers conducting fluid motion in a rapidly rotating spherical shell. The consequence of this exponential dependence of viscosity on temperature is considered to be a thermaldriven convective phenomenon. A set of constitutive non-linear equations were then formulated in which the solutions for the flow variables were obtained by perturbation technique. The results illustrate enhancement of dynamo actions, demonstrating that magnetic field generation with time is possible. Moreover, the increased magnetic Prandtl number Pm with high Brinkman number showsdynamo actions for fixed Rayleigh and Taylor number values. The overall analyses succour our understanding of Earth’s magnetic field generation mechanism often envisaged in the Earth’s planetary interior

View Online
Publication Year
Place Of Publication