Heat and mass transfer for oscillatory convection in a binary viscoelastic fluid layer subjected to temperature modulation at the boundaries.

Weak nonlinear hydrodynamic thermal instability analysis has been performed for double diffusive oscillatory mode of convection in a horizontal layer of viscoelastic fluid, heated from below. Employing complex non-autonomous Ginzburg–Landau equation, effects of various viscoelastic parameters on thermal instability have been investigated. The weak nonlinear analysis reveals that values of viscoelastic parameters have significant effect on the instability. The present study is to investigate the effect of time-periodic temperature modulation on heat and mass transfer, where controlling convection external to the system is important. Sinusoidal profile is taken to modulate the temperature of the boundaries. It is found that the variation of Nusselt number and Sherwood number with respect to the slow time scale becomes rapid as either increasing Rs , Pr , λ , δ or decreasing Γ , ε , Ω . Further, it is found that in-phase temperature modulation has negligible effect, while out of phase temperature modulation and only lower plate temperature modulation have oscillatory effects on heat and mass transport. [ABSTRACT FROM AUTHOR]