Effect of temperature dependent material properties on cold water convection

The effect of temperature dependent material properties on Rayleigh–Bénard convection has been studied for warm water. Great temperature differences between top and bottom boundaries enhance the variation of viscosity and thermal conductivity along the water column, breaking the symmetry of the temperature profile. The main effects are changes in thermal boundary layers and mean temperature.

However, convection also occurs in cold water systems that can be totally or partially ice bounded. In cold water, between 0°C and 4°C, the density anomalies are smaller for a given temperature difference because of the non-linear equation of state. Furthermore, the viscosity and thermal conductivity depend almost linearly on temperature. As a result, the variations in the aforementioned material properties might be important enough to produce measurable effects in convection. Despite its relevance for the ice heat budget on natural systems, the impact of these variations on the heat transfer at the ice-water interface remains unknown. Here we investigate those effects using direct numerical simulations.