TURBULENT STRUCTURE OF AN AXISYMMETRICAL PLUME PENETRATING A STRONG DENSITY STRATIFICATION

The interaction between a turbulent plume and a strong stratified laye r is studied for three experimental configurations with different buoy ancy and ambient stratification. The investigation of the turbulent st ructure of these axisymmetric flows was first carried out under ambien t conditions of high constant density at the origin of the flow. The i nteraction with a stratified environment was then analyzed. The diffic ulty in penetrating the stratified media was due to a large expansion of the flow and a change of the direction of the radial velocity close to the axis. A decrease of the kinetic turbulent energy was observed at the crossing of the neutral zone.