Study by Numerical simulation of the influence of the inclination of a cavity on the convective stability of fluid flow

摘要

In this work, we present a study of natural convection in a rectangular airfilled cell with a Prandtl number Pr = 0.71 and inclined by an angle Φ. The walls for z = 0 and z = H are impermeable and maintained at constant temperatures respectively Th and Tc, while the other two walls are impervious and adiabatic. All walls are assumed to be rigid (Figure 1). The fluid is assimilated to an incompressible Newtonian fluid whose thermophysical characteristics are constant when the temperature difference ΔT = Th-Tc remains sufficiently low (a few degrees) for the Boussinesq approximation to remain applicable. Under these conditions, the convective flows obtained are laminar. Rayleigh is considered between 10~2 ≤ Ra ≤ 10~4 for different inclinations varying from -90° to 180° of aspect ratio A=L/H=10. Our calculations highlight the influence of the angle of inclination on the triggering thresholds of natural convection, the structure of the flow and the heat transfer and thus on the convective instability.