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The role of a second diffusing component on the Gill-Rees stability problem
B M Shankar1, K V Nagamani2, I S Shivakumara3
1Department of Mathematics, PES University, Bangalore, 560 085, India. bmshankar@pes.edu.
Scientific Reports
|November 11, 2022
Summary
The addition of a solute field can destabilize natural convection in porous layers, introducing new instability modes and criteria. This study explores these effects on the Gill-Rees stability problem.
Area of Science:
- Fluid Dynamics
- Heat and Mass Transfer
- Porous Media Physics
Background:
- The Gill-Rees problem investigates natural convection stability in vertical porous layers using a local thermal nonequilibrium model.
- Previous studies focused on thermal effects, leaving the impact of solute concentration unexplored.
Purpose of the Study:
- To analyze the influence of an additional solute concentration field on the Gill-Rees stability problem.
- To uncover novel stability behaviors in double-diffusive convection within porous media.
Main Methods:
- Numerical solution of the stability eigenvalue problem.
- Investigation of the local thermal nonequilibrium model with an added solute field.
Main Results:
- The presence of a solute field can render parallel flow unstable.
- Connected neutral stability curves forming a loop indicate instability regions requiring dual criteria.
- Observed changes in instability modes across different parametric spaces.
Conclusions:
- Solute concentration significantly impacts natural convection stability in porous layers.
- New stability criteria and phenomena emerge under double-diffusive conditions.
- The study reveals complex interactions between thermal and solutal transport in porous media.
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