introduction air pollution has harmful effect on human health and the environment. accordingly, considerable effort has been put to analyze the air pollutants. one important issue is the spatial distribution of these pollutants. dispersion of the pollutants released from sources on the ground is mostly driven by the planetary boundary layer where turbulent flow causes mixing of the content of t...

This study investigates the modifications of the turbulent boundary layer that develops on the suction side of a NACA0015 hydrofoil when a stable partial cavity takes place near the leading edge of the foil. The velocity field measured in non cavitating conditions has been compared with its equivalent in cavitating conditions. A particular focus has been put on the evolution of the logarithmic ...

Granular flow in a rotating tumbler is of theoretical and industrial significance. However, in spite of its relative simplicity, little is known about the dynamics of the top flowing layer. Here we present an experimental study of the velocity field within the fluidized layer of monodisperse particles in a quasi-2D ~two-dimensional! rotating tumbler in the rolling flow regime using particle tra...

We study turbulent flows in a smooth straight pipe of circular cross--section up to $Re_{\tau} \approx 6000$ using direct--numerical-simulation (DNS) the Navier--Stokes equations. The DNS results highlight systematic deviations from Prandtl friction law, amounting about $2\%$, which would extrapolate $4\%$ at extreme Reynolds numbers. Data fitting coefficient yields an estimated von K\'arm\'an ...

We consider the problem of determining the structure of the dark halo of nearby dwarf spheroidal galaxies (dSphs) from the spherical Jeans equations. Whether the dark halos are cusped or cored at the centre is an important strategic problem in modern astronomy. The observational data comprise the line-of-sight velocity dispersion of a luminous tracer population. We show that when such data are ...