Buoyancy effects in turbulent liquid metal flow

The very low ratio of kinematic viscosity to thermal diffusivity

of liquid metals proves favorable in applications of heat

transfer, especially for high thermal loads, and otivates

their application as heat transfer medium. Their low Prandtl

number leads to a scale separation between the velocity and

temperature fi elds with the latter being much smoother than

the former. In buoyancy affected fl ows, this scale separation

lso affects, both, the velocity fi eld and turbulence due to the

buoyancy force term driving the fl ow. To account for these

effects in turbulence models, according data is needed or

their validation. Such data is presented by this work which

investigates the impact of buoyancy on the fl ow of liquid

sodium and heat transfer in the confi gurations of a vertical

backward-facing step and a square duct. Both, the forced and

the mixed convection regime with aiding buoyancy conditions

are considered.