Long and Medium-Term Research: Velocity and Concentration Measurements in the Turbulent Jet and the Jet in Counterflow This award is under the Long and Medium-Term Research at Foreign Centers of Excellence Program, which enables U.S. scientists and engineers to conduct three to twelve months of research abroad at research centers of proven excellence. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve-month postdoctoral research visit by Dr. Minami Yoda of Stanford to work with Dr. Heinrich Fiedler at the Technical University of Berlin. Their research project involves development of techniques for the simultaneous acquisition of two-dimensional concentration and velocity fields for application in turbulent water flows. This technique will initially be developed in a fundamental flow, the axisymmetric jet, to evaluate its accuracy and applicability. They will then use their technique to investigate the jet in counterflow, a new flow which is of interest because it displays transition from convective to absolute instability. In both cases their approach will involve marking the flows first with flueorescent dye to measure the two-dimensional (passive scalar) concentration field, then with neutrally buoyant particles to measure the velocity field, and finally with a combination of the two to acquire both fields at once. The results from this new technique will clarify the role of convective mixing in turbulent free shear flows. The award recommendation provides funds to cover international travel and a stipend for twelve months.
