Cavity with vertical temperature gradient at Ra = 10^4: velocity and temperature fields

Imagine a rectangular cavity with dimensions (2LxL), in which air is completely enclosed (Prandtl number is 0.71). The upper wall is at temperature (T_cold), and the lower wall is at temperature (T_hot).
Using the numerical methods I have learned at the CTTC - UPC, the following video simulates the non-dimensional temperature field, as well as the velocity field, both independent of grid and time step, starting at static initial conditions, for a Rayleigh number of 10^4.