caa a22 4500 445812052 CHVBK 20180317145215.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s00419-010-0425-8 doi (NATIONALLICENCE)springer-10.1007/s00419-010-0425-8 Coriolis effect on thermal convection in a couple-stress fluid-saturated rotating rigid porous layer [Elektronische Daten] [I. Shivakumara, S. Sureshkumar, N. Devaraju] Both linear and weakly nonlinear stability analyses are performed to study thermal convection in a rotating couple-stress fluid-saturated rigid porous layer. In the case of linear stability analysis, conditions for the occurrence of possible bifurcations are obtained. It is shown that Hopf bifurcation is possible due to Coriolis force, and it occurs at a lower value of the Rayleigh number at which the simple bifurcation occurs. In contrast to the nonrotating case, it is found that the couple-stress parameter plays a dual role in deciding the stability characteristics of the system, depending on the strength of rotation. Nonlinear stability analysis is carried out by constructing a set of coupled nonlinear ordinary differential equations using truncated representation of Fourier series. Sub-critical finite amplitude steady motions occur depending on the choice of physical parameters but at higher rotation rates oscillatory convection is found to be the preferred mode of instability. Besides, the stability of steady bifurcating equilibrium solution is discussed using modified perturbation theory. Heat transfer is calculated in terms of Nusselt number. Also, the transient behavior of the Nusselt number is investigated by solving the nonlinear differential equations numerically using the Runge-Kutta-Gill method. It is noted that increase in the value of Taylor number and the couple-stress parameter is to dampen the oscillations of Nusselt number and thereby to decrease the heat transfer. Springer-Verlag, 2010 Couple-stress fluid nationallicence Porous medium nationallicence Rotation nationallicence Hopf bifurcation nationallicence Nonlinear stability nationallicence Shivakumara I. UGC-Centre for Advanced studies in Fluid Mechanics, Department of Mathematics, Bangalore University, 560001, Bangalore, India aut Sureshkumar S. Department of Mathematics, Siddaganga Institute of Technology, 572103, Tumkur, India aut Devaraju N. UGC-Centre for Advanced studies in Fluid Mechanics, Department of Mathematics, Bangalore University, 560001, Bangalore, India aut Archive of Applied Mechanics Springer-Verlag 81/4(2011-04-01), 513-530 0939-1533 81:4<513 2011 81 419 https://doi.org/10.1007/s00419-010-0425-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00419-010-0425-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shivakumara I. UGC-Centre for Advanced studies in Fluid Mechanics, Department of Mathematics, Bangalore University, 560001, Bangalore, India aut NATIONALLICENCE 700 1- Sureshkumar S. Department of Mathematics, Siddaganga Institute of Technology, 572103, Tumkur, India aut NATIONALLICENCE 700 1- Devaraju N. UGC-Centre for Advanced studies in Fluid Mechanics, Department of Mathematics, Bangalore University, 560001, Bangalore, India aut NATIONALLICENCE 773 0- Archive of Applied Mechanics Springer-Verlag 81/4(2011-04-01), 513-530 0939-1533 81:4<513 2011 81 419 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer