A review on natural convection in enclosures for engineering applications. The particular case of the parallelogrammic diode cavity

• Natural convection in enclosures. Large collection of studies on cavities of different shapes.
• Engineering applications.
• Analysis of the results obtained from different solving techniques.
• Review of parallelogram-shaped, natural convective diode cavity.
• Influence of the main physical parameters on the natural convective heat transfer.

This paper presents a review of some results of research on natural convection in cavities. The compilation serves to underline the broad spectrum of scientific and engineering fields where the knowledge of natural convection in enclosures is advantageously applied. The principal cavity geometries treated in the literature and their effect on the flow features are revisited. A great variety of configurations of the enclosures with different shapes and inclinations, thermal boundary conditions, initial conditions, heat source distributions, nature of the fluid and radiative properties, are examined. The review also considers the achievements and limitations of the different experimental, numerical, analytical and inverse methods approaches used when dealing with this problem. Published works cover a wide range of Rayleigh numbers going from rather simple laminar, steady-state cases to highly unstable, transient and turbulent flows.The review is particularly devoted to the parallelogram-shaped cavity, also called convective diode cavity, and hence a comprehensive list of published works is provided for this case.