Effects of variable internal heat source and variable gravity field on convection in a porous layer

H. Nagarathnamma; Y. H. Gangadharaiah; K. Ananda

doi:10.26637/MJM0803/0031

Abstract

The present article is to examine the qualitative impact of variable internal heat source and gravity variance field on the onset of convection in a horizontal fluid saturated porous medium is investigated using linear stability analysis. To measure the value of the critical Rayleigh number and the corresponding wave number, the single term Galerkin technique is used. Eight separate sets of gravity variance and heat source functions are chosen, and their effect is addressed on the onset of convection. It is observed that the variable heat source and variable gravity at the start of convection do not affect the shape and size of the convective cell. It seen that the system is to be more unstable for the caseses (ii), (iii), (vi) and (vii) while more stable for the caseses (i), (iv), (v) and (viii).

Keywords:

Variable internal heat source, Variable gravity, Heat transfer, Stability

Mathematics Subject Classification:

Mathematics

Authors Imprint References Funding Related Articles Downloads

H. Nagarathnamma Department of Mathematics, Dr. Ambedkar Institute of Technology, Bangalore-560056, India.
Y. H. Gangadharaiah Department of Mathematics, Sir M. Visvesvaraya Institute of Technology, Bangalore-562157, India. https://orcid.org/0000-0003-0018-4527
K. Ananda Department of Mathematics, New Horizon College of Engineering, Bangalore-560103, India.

Pages: 915-919
Date Published: 01-07-2020
Vol. 8 No. 03 (2020): Malaya Journal of Matematik (MJM)

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