Leo H. O. Hellström, a) Bharathram Ganapathisubramani, b) and Alexander J. Smits c) Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, U.S.A. Faculty of Engineering and the Environment, University of Southampton, Southampton, SO17 1BJ, U.K. Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, U.S.A., and Mechanical and Aerospace Engineer...

Several experimental and numerical studies have shown that turbulent motions in circular pipe flow near transitional Reynolds numbers may not persist forever, but may decay. We study the properties of these decaying states within direct numerical simulations for Reynolds numbers up to 2200 and in pipes with lengths equal to 5, 9, and 15 times the diameter. We show that the choice of the ensembl...

flow visualization techniques using tracer markers such as die, smoke, hydrogen bubbles, etc., have been widely used in experimental investigations of large scale structures of a variety of flow fields. they have played an important role in understanding the physics of the coherent structures formation and evolution in the transitional as well as the turbulent regions of the flow fields. howeve...

The new semi-experimental method for simulation of the turbine flow meters rotation in the transitional flow has been developed. The method is based on the experimentally established exponential low of changing of dimensionless relative turbine gas meter rotation frequency and meter inertia time constant. For experimental evaluation of the meter time constant special facility has been developed...

Flow visualization techniques using tracer markers such as die, smoke, hydrogen bubbles, etc., have been widely used in experimental investigations of large scale structures of a variety of flow fields. They have played an important role in understanding the physics of the coherent structures formation and evolution in the transitional as well as the turbulent regions of the flow fields. Howeve...

Haemodynamic forces appear to play an influential role in the evolution of aneurysms. This has led to numerous studies, usually based on computational fluid dynamics. Their focus is predominantly on the wall shear stress (WSS) and associated derived parameters, attempting to find correlations between particular patterns of haemodynamic indices and regions subjected to disease formation and prog...

Direct numerical simulation (DNS) is used to study the effect of individual (hemispherical) and distributed roughness on supersonic flat plate boundary layers. In both cases, roughness generates a shear layer and counter–rotating pairs of unsteady streamwise vortices. The vortices perturb the shear layer, resulting in trains of hairpin vortices and a highly unsteady flow. Mach 3.37 flow past a ...

Dispersion and mixing of inertial point particles in the unsteady three-dimensional wake a circular cylinder at $Re=200$ are investigated via one-way coupled simulations. The presence streamwise-oriented vortical braids originating from mode A instability transition regime has profound impact on particle dynamics preferential concentration near wake. Particles trapped between Kármán rollers str...