Oscillatory Double-Diffusive Convection in a Horizontal Cavity with Soret and Dufour Effects

TL;DR

This study numerically investigates oscillatory double-diffusive convection in a horizontal cavity, revealing how flow patterns transition from steady to chaotic states influenced by buoyancy ratio, Rayleigh number, and aspect ratio.

Contribution

It introduces a detailed numerical analysis of oscillatory double-diffusive convection considering Soret and Dufour effects, highlighting flow transitions and frequency behaviors.

Findings

Flow transitions from steady to chaotic with increasing buoyancy ratio.

Fundamental frequency and fluctuation amplitude depend on buoyancy ratio and aspect ratio.

Transition trends of oscillatory convection are similar to Rayleigh number effects, but return to periodic oscillation from chaos is not observed at higher Rayleigh numbers.

Abstract

Oscillatory double-diffusive convection in horizontal cavity with Soret and Dufour effects is investigated numerically based on SIMPLE algorithm with QUICK scheme in non-uniform staggered grid system. The results show that double-diffusive convection develops from steady-state convection-dominated, periodic oscillatory, quasi-periodic oscillatory to chaotic flow, and finally return to periodic oscillation as buoyancy ratio increases. Moreover, fundamental frequency and fluctuation amplitude increase with buoyancy ratio. As Rayleigh number increases, transition trendy of oscillatory convection is similar to that of buoyancy ratio. But the return of periodic oscillation from chaos is not obtained as Rayleigh number increases. As aspect ratio decreases, the oscillatory convection evolves from periodic into steady-state. In addition, fundamental frequency increases at first and then decreases while fluctuation amplitude decreases with aspect ratio.