Direct numerical simulations of the transition process from periodic to chaotic dynamics are presented for two variable Oregonator-diffusion model coupled with convection. Numerical solutions to the corresponding reaction-diffusion-convection system of equations show that natural convection can change in a qualitative way, the evolution of concentration distribution, as compared with convection...

The effects of natural convection with and without the interaction of surface radiation in square and rectangular enclosures have been studied, numerically and theoretically. The analyses were carried out over a wide range of enclosure aspect ratios ranging from 0.0625 to 16, including square enclosures in sizes from 40cm to 240cm, with cold wall temperatures ranging from 283 to 373 K, and hot ...

Steady state experiments have been conducted for natural and mixed convection heat transfer, from five different sized protruding discrete heat sources, placed at the bottom position on a PCB and mounted on a vertical channel. The characteristic length ( Lh ) of heat sources vary from 0.005 to 0.011 m. The study has been done for different range of Reynolds number and modified Grashof number. F...

The figures on the left show effect of Prandtl number (Pr) Rayleigh-B\'enard problem with Boussinesq conditions, for same Grashof ${10}^{9}$. Top: Pr = 12.73; bottom, ${10}^{\ensuremath{-}4}$. plot right shows that low molecular yields an inversely varying turbulent number; is, flow behaves effectively as a high fluid. data are non-Boussinesq conditions. qualitative is case well, but dependence...

Pollution occurs when the concentration of various chemical or biological constituents exceed a level implying negative impact on amenities, the eco-system, resources and human health. Oil spills are the serious environmental   hazards which often exhibit long-term impacts. The main objective of response to an oil spill is to reduce its impact on nature and human health. This paper allows us to...

In the present research mixed convection flow through a copper-water nanofluid in a driven cavity in the presence of magnetic field is investigated numerically. The cavity is heated from top and cooled from bottom while its two vertical walls are insulated. The governing equations including continuity, N-S and energy equations are solved over a staggered grid system. The study is conducted for ...

Three consequent bifurcations of buoyancy convection in a laterally heated cube with perfectly thermally insulated boundaries are studied. With the growth Grashof number, flow becomes oscillatory unstable, then stability reinstates at larger further increase which finally unstable. It is shown that all three transitions result from an interaction between destabilizing centrifugal mechanism and ...

The paper studied the transient convection fluid flow with heat flux in an infinite vertical plate with chemical mass transfer. The dimensionless governing equations were solved using the Laplace transform method to obtained the analytical expressions of velocity, temperature and concentration profiles of the fluid with expression of Skin friction, mass and heat transfer in terms of Shear stres...

Numerical study of the slip effects and radiative heat transfer on a steady state fully developed Williamson flow of an incompressible Newtonian fluid; between parallel vertical walls of a microchannel with isothermal walls in a porous medium is performed. The slip effects are considered at both boundary conditions. Radiative highly absorbing medium is modeled by the Rosseland approximation. Th...

A free convective unsteady visco-elastic flow through porous medium bounded by an infinite vertical porous plate with variable suction, constant heat flux under the influence of transverse uniform magnetic field along with permeability in the presence of radiation has been investigated in the present study. The suction velocity of the porous medium fluctuates with time about the constant mean. ...