Two transitions of thermosolutal natural convection in the presence of an external magnetic field

Page:

120-125

DOI:

http://doi.org/10.18280/mmep.040302

OPEN ACCESS

Abstract:

This paper presents a numerical study of two transitions (onset/oscillatory) of thermosolutal natural convection (TSNC) under the effect of an external magnetic field (MF) in binary mixture. For this, a square enclosure filled with a binary mixture has been considered and exposed to opposing solute and thermal gradients. An external and uniform MF is applied separately in two directions, i.e., vertical and horizontal. The results are given for varying buoyancy ratio (N = 0.75, 1.0 and 1.25), Prandtl number (Pr = 0.71) and Schmidt number (Sc = 3.5). The obtained results show a good agreement with the experimental data available in the literature. We show a strong effect of the buoyancy ratio on the flow field, the thermal and solute structure. The onset of TSNC and oscillatory TSNC flow are determined, and then the oscillatory flow occurs for a periodic time evolution where the phenomena change around in each period time.

Keywords:

*Thermosolutal Natural Convection (TSNC), Magnetic Field (MF), Oscillatory Flows, Onset Flow,
Buoyancy Ratio*

1. Introduction

2. Problem Statement and Modeling

3. Numerical Solution Technique

4. Results and Discussion

5. Conclusion

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