Summary: Experimental measurements and numerical simulations of natural convection in a cubical cavity heated from below and cooled from above are reported at turbulent Rayleigh numbers using water as a convective fluid (Pr = 6.0). Direct numerical simulations were carried out considering the Boussinesq approximation with a second-order finite volume code \((10^{7}\leq Ra \leq 10^{8})\). The particle image velocimetry technique was used to measure the velocity field at \(Ra = 10^{7}\),\( Ra = 7 \times 10^{7}\) and \(Ra = 10^{8}\) and there was general agreement between the predicted time averaged local velocities and those experimentally measured if the heat conduction through the sidewalls was considered in the simulations.