The paper addresses the Large-Eddy Simulation (LES) of the turbulent wake of the Ahmed car model. To this endwe use a Fourier-Chebyshevmulti-domain solver and the LES capability is implemented through the use of the Spectral Vanishing Viscosity (SVV) method, completed with a near-wall correction. A “pseudo-penalization” technique is used to model the bluff body. Comparisons of the present SVV-L...

The nonlinearity of the Navier-Stokes equations makes predicting the flow of fluid around rapidly moving small bodies highly resistant to all approaches save careful experiments or brute force computation. Here, we show how a linearization of the Navier-Stokes equations captures the drag-determining features of the flow and allows simplified or analytical computation of the drag on bodies up to...

The interaction between wakes of bluff body and airfoil have profound influences on system performance in many industrial applications, e.g., turbo-machinery and cooling fan. The present work investigates the effect of configuration include; airfoil’s angle of attack, transverse and inline spacing of the models, on frequency behavior of the cylinder’s near-wake. The experiments carried on under...

An exponentially convergent observer is designed for a linearized Ginzburg-Landau model of vortex shedding in viscous flow past a bluff body. Measurements are restricted to be taken collocated with the actuation which is applied on the cylinder surface. The observer is used in conjuction with a state feedback boundary controller designed in previous work to attenuate vortex shedding. Simulation...

We present a novel multiresolution Vortex-In-Cell algorithm using patches of varying resolution. The Poisson equation relating the fluid vorticity and velocity is solved using Fast Fourier Transforms subject to free space boundary conditions. Solid boundaries are implemented using the semi-implicit formulation of Brinkman penalization and we show that the penalization can be carried out as a si...

A combined analytical-experimental approach is used. Analytical aspects focus on the continued development of a low-order model that utilizes a series of diffusively coupled circle map oscillators along the cylinder span. This coupled map lattice has been extended to include control logic to develop a very efficient low order model for control studies in cylinder wake flows. On the experimental...

A vortex method with penalization is proposed in order to simulate three-dimensional incompressible bluff body flows. This approach combines the robustness of vortex methods and the flexibility of penalization methods to impose boundary conditions on the obstacle. Far field boundary conditions are handled in a FFT-based Poisson solver. A validation of the proposed numerical method is carried ou...