Experimental study of a laminar jet in a double-diffusion environment

An experimental analysis of the flow development caused by the simultaneous injection and withdrawal of a buoyant fluid layer with low Reynolds number in a double-diffusion environment is presented. The injection of positively, neutrally, and negatively buoyant fluid layers was simulated in the experimental setup. Innovative procedures were developed to efficiently create the desired density distributions in the laboratory flume. Results presented in this paper concern the injection of fluid into environments stratified by temperature, salinity or both. Basic features of the flow patterns are described, in particular, intrusion rate, effect on ambient stratification and vertical displacement. The experimental data on the fluid vertical displacement were compared with results from a numerical model and good agreement was found.