The diffuse background radiation is observed throughout the whole sky and across every wavelength of the electromagnetic spectrum. The study of this background is of great importance as it contains photons coming from a variety of astrophysical environments, traveling over the time scales of a few hundred light years to the age of the universe itself. After the discover of the cosmic microwave background, the diffuse sky in all the other wavelengths was studied with great interest as the could provide useful insights into the formation history of the universe.
The thesis is concerned with Rayleigh-Benard convection in a horizontal porous layer saturated with a viscoelastic fluid subject to a zero order exothermic chemical reaction. Modified Darcy law is employed to describe the fluid motion. The effect of viscoelasticity, chemical reaction, and rotation on the onset of convection is considered. The findings of the problems investigated in the thesis may prove useful in heat transfer application situations with viscoelastic fluids as working medium.
