Density currents over complex terrain - IfH

GOAL AND METHODS: Goal of this work, is to enhance the understanding of the instabilities due to shear
and flow curvature (Goertler, Kelvin-Helmholtz, and Holmboe), and vertical mixing generated at the front
and at the shear layer of such density currents. This will be achieved through physical experiments using
optical non-intrusive measurements techniques (LIF and PIV) in a plane. Present available equipment
include a horizontal channel 0.40 m wide, 0.50 m high and 6 m long, with equipment for linear or two-layer
stratification, a 5W Argon Ion laser which will enable PIV and PLIF measurements to capture the velocity
and density fields. Density currents will be generated using saline solutions in a fresh water ambient. We
will consider various slope steepnesses and stratification conditions in ambient fluid. Detailed tasks which
has to be handled by the candidate are given in the following.
• Literature review: review of literature and existing experimental work.
• PIV Experiments: acquisition of velocity data for different stratification conditions and topographies.
• Visualizations: using fluorescent dye.
• Data Post-Processing: Analysis of the acquired data:
• image processing (from dye visualizations) and qualitative description
• mean values and time analysis,
• identification of the instabilities in the parameter space,
• entrainment and mixing
• Discussion and intepretation of the results
SUPERVISION
Dr. Ing.-Eletta Negretti, Tel.: +33(0)4 76 82 86 54, maria-eletta.negretti@legi.grenoble-inp.fr.
Location: GRENOBLE, FRANCE.
Ansprechparter am Institut für Hydromechanik (IfH), KIT:
Dr.-Ing. Cornelia Lang, Tel. 0721 608 43845, Cornelia.Lang@kit.edu