stratified fluid layer because of selective absorption of radiation was conducted by Krishnamurti [ 10 ]. The convection mechanism observed by Krishnamurti was a penetrative one, which was, stimulated by internal heating through absorption of radiation. Penetrativeconvection is a phenomenon that arises when buoyancy-driven motion penetrates into stratified layers [ 11 ]. In the experimental work, Krishnamurti considered a layer of water that contains a pH indicator known as thymol blue. This model of Krishnamurti was again investigated by Straughan [ 12 ] with the
We present an investigation of dynamo in a simultaneous dependence on the non-uniform stratification, electrical conductivity of the inner core and the Prandtl number. Computations are performed using the MAG dynamo code. In all the investigated cases, the generated magnetic fields are dipolar. Our results show that the dynamos, especially magnetic field structures, are independent in our investigated cases on the electrical conductivity of the inner core. This is in agreement with results obtained in previous analyses. The influence of non-uniform stratification is for our parameters weak, which is understandable because most of the shell is unstably stratified, and the stably stratified region is only a thin layer near the CMB. The teleconvection is not observed in our study. However, the influence of the Prandtl number is strong. The generated magnetic fields do not become weak in the polar regions because the magnetic field inside the tangent cylinder is always regenerated due to the weak magnetic diffusion.
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 Mahajan, A., Nandal, R. (2017). On the stability of penetrativeconvection in a couple-stress fluid. International Journal of Applied and Computational Mathematics 3(4), 3745-3758.
Mahajan A. Nandal R. 2017 On the stability of penetrativeconvection in a couple-stress fluid International Journal of Applied and Computational Mathematics 3 4 3745 3758
 Nandal, R., Mahajan, A. (2018). Penetrativeconvection in couple-stress fluid