Effects of Brinkman number on thermal-driven convective spherical Dynamos.

Journal of Applied Sciences and Environmental Management

NGWUEKE, M.I.¹  ABBEY, T.M.¹ 

关键词: Magnetic field generation;    Thermal-driven convection;    Brinkman number;    Dynamo action;    Fluid outer core;   

DOI  :  

学科分类：环境科学（综合）

来源: University of Port Harcourt * Department of Pure and Industrial Chemistry

【 摘 要 】

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 bythe 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. Theconsequence of this exponential dependence of viscosity on temperature is considered to be a thermaldrivenconvective 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 shows dynamo 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.© JASEM

【 授权许可】

Unknown