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Analytic Solutions and Entropy Production of the Double-Diffusive Equation System
Imre Ferenc Barna1, László Mátyás2
1Hungarian Research Network, Wigner Research Centre for Physics, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary.
Entropy (Basel, Switzerland)
|September 27, 2025
Summary
This study analyzes double-diffusion convection using a reduction formalism, presenting analytic results for fluid dynamics and entropy production. An additional heat source
Area of Science:
- Fluid dynamics
- Thermodynamics
- Partial Differential Equations
Background:
- Double-diffusion convection involves density gradients driven by two scalar quantities with differing diffusivities (e.g., heat and solute).
- Understanding these phenomena is crucial in various fields, including geophysics and materials science.
Purpose of the Study:
- To investigate the partial differential equation system governing double-diffusion convection.
- To derive analytic solutions for dynamical variables and entropy production.
- To explore the impact of an additional heat source on the system.
Main Methods:
- Application of the reduction formalism.
- Utilizing time-dependent self-similar trial functions.
- Derivation of analytic results for dynamical variables and entropy production.
Main Results:
- Analytic solutions were obtained for the dynamical variables.
- Entropy production was derived and analyzed.
- The influence of an additional heat source was investigated.
Conclusions:
- The reduction formalism provides an effective method for analyzing double-diffusion convection.
- The study presents a comprehensive analytic framework for understanding these complex fluid dynamics.
- Further research can extend this model to include more complex boundary conditions or additional physical effects.
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