An immersed boundary technique is used to model a riblet covered surface on one wall of a channel bounding fully developed turbulent flow. The conjecture that the beneficial drag reduction effect of… (More)

A variety of chaotic flows evolving in relatively high-dimensional spaces are considered. It is shown through the use of an optimal choice of basis functions, which are a consequence of the… (More)

In many situations involving flows of high Reynolds number (where inertial forces dominate over viscous forces), such as aircraft flight and the pipeline transportation of fuels, turbulent drag is an… (More)

In view of the “observations” of the Cornell group, reassessment of their and our models for wall-bounded turbulence has been made. Wide ranging evidence is presented for the existence and key role… (More)

The dynamical equations for the energy in a turbulent channel ow have been developed by using the Karhunen-Lo eve modes to represent the velocity eld. The energy balance equations show that all the… (More)

Turbulent solutions of the one-dimensional complex Ginzburg-Landau equation when the dissipation is very small aie considered. It is found that probability distributions are strictly Gaussian,… (More)

We investigate a sequence of low-dimensional models of turbulent channel flows. These models are based on the extraction of the Karhunen–Lo` eve (KL) eigenfunctions from a large-scale simulation in a… (More)

The rnapshot method is used to analyze a large eddy simulation of axisymmetric jet flow. An ensemble of realizations is collected using a sampling condition that corresponds to the passage of a large… (More)