Showing papers in "Computers & Fluids in 2006"

TL;DR: In this article, the capability and accuracy of the lattice Boltzmann equation (LBE) for modeling flow through porous media was evaluated with the multiple-relaxation-time (MRT) and Bhatnagar-Gross-Krook (BGK) collision operators.

TL;DR: In this article, numerical simulations of the 2D lid-driven cavity flow are performed for a wide range of Reynolds numbers and the first Hopf bifurcation is localized by a study of the linearized problem.

TL;DR: In this article, the gappy POD is extended to handle unsteady flow reconstruction problems, such as those encountered when limited flow measurement data is available, and a systematic approach for effective sensor placement is formulated within the Gappy framework using a condition number criterion.

TL;DR: This report presents a comprehensive survey of the effect of different data layouts on the single processor performance characteristics for the lattice Boltzmann method both for commodity “off-the-shelf” (COTS) architectures and tailored HPC systems, such as vector computers.

TL;DR: In this article, the authors extended the Lattice Boltzmann (LB) method to simulate multi-phase flows on non-uniform tree-type grids, and showed that the maximum number of possible grid levels for problems with dominant capillary forces is very restricted if the physical interface is allowed to pass over grid interfaces.

TL;DR: In this paper, an isothermal circular jet with a Mach number of M = 0.9 and a Reynolds number of ReD = 4 · 10 5 is computed by compressible large eddy simulation (LES).

TL;DR: An optimized explicit low-storage fourth-order Runge–Kutta algorithm is proposed in the present work for time integration and Dispersion and dissipation of the scheme are minimized in the Fourier space over a large range of frequencies for linear operators while enforcing a wide stability range.

TL;DR: In this paper, the authors compare the accuracy and computational efficiency of two research simulation codes based on the LB and the finite element method (FEM) for two-dimensional incompressible laminar flow problems with complex geometries.

TL;DR: In this article, the authors present unsteady flow simulations at the rear slant angles 25° and 35° using the PowerFLOW 4.0 D3Q19 lattice Boltzmann model.

TL;DR: In this article, the authors considered the application of multiple-relaxation-time (MRT) lattice Boltzmann equation (LBE) for large-eddy simulation (LES) of turbulent flows.

TL;DR: In this article, a simple and effective iterative procedure was proposed to generate consistent initial conditions for the lattice Boltzmann equation (LBE) for incompressible flows with a given initial velocity field u0.

TL;DR: A state-of-the-art method for solving the preconditioned compressible Navier–Stokes equations accurately and efficiently for a wide range of the Mach number with an immersed-boundary approach which allows one to use Cartesian grids for arbitrarily complex geometries is combined.

TL;DR: In this article, the effects of the gap ratio s / d ( s is the separation between the cylinders and d is the characteristic dimension) on the flow of two square cylinders placed side-by-side were investigated using the lattice Boltzmann method.

TL;DR: In this article, a new class of schemes, the residual distribution schemes, adapted to compressible flow problems, is discussed, which can be seen as a link between pure finite element methods such as the streamline diffusion method and the high order upwind method finite volume schemes.

TL;DR: In this paper, a large eddy simulation (LES) is performed to study the uniform approach flow over a square-section cylinder with different Reynolds numbers, ranging from 10 3 to 5 ǫ×10 6, and two different sub-grid scale models, the Smagorinsky and a dynamic one-equation model, are employed.

TL;DR: In this article, large-eddy simulations of a jet in a cross-flow (JICF) problem are carried out to investigate the turbulent flow structure and the vortex dynamics in gas turbine blade film cooling.

TL;DR: In this article, an unsteady Reynolds-averaged Navier-Stokes method is developed to compute motions and the resulting flow and wave fields around surface ships, which is used for the viscous phenomenon of roll decay motion for a surface combatant.

TL;DR: In this paper, the effect of the aspect ratio and Reynolds number on the size, center position and number of vortices in a lid-driven rectangular cavity at different depth-to-width ratios and Reynolds numbers was investigated using a lattice Boltzmann method.

TL;DR: A new volume tracking method is introduced for tracking interfaces in three-dimensional (3D) geometries partitioned with orthogonal hexahedra using fully multidimensional fluxes that have their definition based in backward-trajectory remapping.

TL;DR: In this paper, an implicit dual time stepping scheme combined with low Mach number preconditioning and a multigrid acceleration technique is proposed for low subsonic turbulent flows.

TL;DR: In this paper, the results of direct numerical simulations (DNS), by a lattice Boltzmann scheme, of fully developed, incompressible, pressure-driven turbulence between two parallel plates, are validated against results from simulations using a standard Chebyshev pseudo-spectral method.

TL;DR: In this paper, a Cartesian grid method with cut cell approach has been developed to simulate two dimensional unsteady viscous incompressible flows with rigid bodies of arbitrary shape.

TL;DR: In this paper, an automatic optimization procedure coupled with the flow solver is employed to optimize the parameters of the actuator (momentum coefficient, frequency, angle with respect to the wall) at each incidence in order to increase the time-averaged lift.

TL;DR: In this paper, the piece-wise parabolic method is applied to simulations of forced isotropic turbulence with Mach numbers ∼ 0.1 − 1.7, and the authors find the bottleneck phenomenon, i.e., a flattening of the spectrum function near the wave number of maximal dissipation.

TL;DR: This work proposes an alternative way of discretizing the convection operator using an upwind scheme, as opposed to the central scheme described by Peng et al, which works on unstructured grids, thus allowing an increased geometrical flexibility.

TL;DR: In this paper, the accuracy of an equal-order finite element method based on piecewise quadratic shape functions with local projections stabilization on locally refined meshes for stationary laminar flows around an obstacle with circular and square cross-section was investigated.

TL;DR: In this paper, the numerical solution of highly nonlinear parabolic equations with Lattice Boltzmann techniques is addressed, and the analysis of boundary continuity conditions by using anisotropic LB techniques are applied to Richardson's equation for variably saturated flow.

TL;DR: In this paper, the lattice Boltzmann equation (LBE) method is applied for simulation of lid-driven flow in a two-dimensional, rectangular, deep cavity.

TL;DR: In this article, two separate sets of numerical experiments on the collision of a dipole with a no-slip boundary at several Reynolds numbers were performed with finite differences codes and with a Chebyshev pseudospectral code.

TL;DR: In this paper, the effects of electron density fluctuations on electromagnetic wave propagation in turbulent plasma media during reentry is investigated, where the authors focus on the effect of electron densities on the propagation of electromagnetic wave in high velocity flight vehicles.