Three-dimensional evolution of flow structures in transitional circular and chevron jets

The three-dimensional behavior of flow transition in circular and 6-chevron jets at Re?=?5000 is investigated with experiments conducted on a free water jet by time-resolved tomographic particle image velocimetry. The emphasis is on the unsteady organization of coherent flow structures, which play a role in the generation of acoustic noise....

Dynamics of prolate ellipsoidal particles in a turbulent channel flow

The dynamical behavior of tiny elongated particles in a directly simulated turbulent flow field is investigated. The ellipsoidal particles are affected both by inertia and hydrodynamic forces and torques. The time evolution of the particle orientation and translational and rotational motions in a statistically steady channel flow is obtained for...

Wind and boundary layers in Rayleigh-Bénard convection. II: Boundary layer character and scaling

Wind and boundary layers in Rayleigh-Bénard convection. I: Analysis and modeling

A linear approach for the evolution of coherent structures in shallow mixing layers

The development of large coherent structures in a shallow mixing layer is analyzed. The results are validated with experimental data obtained from particle tracking velocimetry. The mean flow field is modeled using the self-similarity of the velocity profiles. The characteristic features of the down-stream development of a shallow mixing layer...

Experiments on Unsteady Seperating Flow in an Open Channel

Experiments on unsteady separating flow past a sudden expansion in an open channel are described. To simulate tidal flow the flow rate in the approach channel varied as a half-sine with time. Different visualization techniques to obtain an insight into the behaviour of the separating vortex in time and space were used. Laser-Doppler velocimetry ...