▪ Abstract We review the experimental evidence on turbulent flows over rough walls. Two
parameters are important: the roughness Reynolds number ks+, which measures the effect …

Direct numerical simulations of turbulent flow over regular arrays of urban-like, cubical
obstacles are reported. Results are analysed in terms of a formal spatial averaging …

Results are presented from an experimental study of shallow flow in a channel partially
obstructed by an array of circular cylinders. The cylinder array is a model for emergent …

The structure of turbulent flow over large roughness consisting of regular arrays of cubical
obstacles is investigated numerically under constant pressure gradient conditions. Results …

Interactions between turbulent waters and atmosphere may lead to strong air–water mixing.
This experimental study is focused on the flow down a staircase channel characterised by …

Turbulent flow in a channel with transverse rib roughness on one wall is investigated by
large-eddy simulation (LES). The spacing of the roughness elements is varied to reproduce …

Results of an experimental investigation of the flow over a model roughness are presented.
The series of roughness consists of close-packed pyramids in which both the height and the …

Turbulence data from experiments conducted over a staggered cube array, modelling a
neutrally stable atmospheric boundary layer in an urban environment, are presented. The …

DNS results for turbulent channel flow with two-and three-dimensional roughness elements
are discussed. The focus is on surfaces where the separation between consecutive …

A fully turbulent channel flow with smooth and rod-roughened walls has been investigated
using hot-wire anemometry and direct numerical simulations (DNS). The mean flow follows …