Department of Mechanical Engineering Spring Seminar Series
“Experimental Methods in Thermal-Fluid Sciences”
Presented by Professor Matthieu Andre, Mechanical and Aerospace Engineering Department, The George Washington University
There exists a wide range of measurement techniques applied to fluid mechanics, each with its advantages and drawbacks. In this seminar, some examples of advanced optical techniques covering very diverse aspects of thermal-fluid sciences are presented.
In the first part, time-resolved particle image velocimetry (PIV) coupled to planar laser induced fluorescence (PLIF) is applied to a free surface flow to study fundamental physics responsible for atomization and air entrainment. High spatio-temporal resolution PIV data in both phases and precise reconstruction of the interface give new understandings of bubble entrainment caused by shear layer instability below the surface.
The second part discusses the use of molecular tagging velocimetry (MTV) to probe gas-cooled nuclear reactors in accident scenarios. This applied research aims at measuring in a large test facility the slow flow transient following a loss of forced circulation of the coolant. The diagnostics capabilities and performances are first assessed in the lab, and then the technique is deployed to perform in-situ measurements, providing valuable validation data for the models used in the design of such reactors.
Finally, a new experimental facility for fluid-structure interaction studies is described, and examples of optical measurements applied to other research areas are presented.
Matthieu Andre is a research professor in the Mechanical and Aerospace Engineering department at The George Washington University in Washington D.C. He received his M.S. degree from the Ecole Centrale de Lille in France in 2010, and obtained his Ph.D. in Mechanical Engineering from the George Washington University in 2014. His work focuses on experimental fluid mechanics and his current research interests include multiphase flows (e.g. cavitation, stratified flows, free surface flows), buoyant flows, and the development of experimental measurement techniques. He has experience with many laser-based diagnostics such as PIV, MTV, PLIF, Rayleigh scattering, and tunable diode laser absorption spectroscopy. His work was published in prominent journals such as Journal of Fluid Mechanics, Physics of Fluids, Experiments in Fluids, Measurement Science and Technology, and International Journal of Multiphase Flow. He received the best presentation award at the Young Professional Thermal Hydraulics Research Competition at the 2013 ANS winter meeting, and was a winner of the 2013 GW SEAS R&D Showcase for his work on free surface flow instabilities.