Showing papers in "Computers & Fluids in 1998"

TL;DR: A level set method for capturing the interface between two fluids is combined with a variable density projection method to allow for computation of a two-phase flow where the interface can merge/break and the flow can have a high Reynolds number.

TL;DR: In this paper, a Chebyshev collo-cation method was used to compute high-accuracy solutions for the lid-driven cavity flow by using a substraction method of the leading terms of the asymptotic expansion of the solution of the Navier-Stokes equations in the vicinity of the corners.

TL;DR: In this article, a numerical algorithm is presented for the solution of geometrically challenging two-dimensional river and estuary flows, based on an adaptive triangular tessellation of the flow domains of interest.

TL;DR: In this paper, the authors analyzed six cases of turbulent flows over backward-facing steps and in sudden plane and axisymmetric expansions at a range of Reynolds numbers, using two variants of high Re number second-moment closures and a new model which accounts separately for low- Re number, wall blockage and pressure reflection effects, thus allowing integration up to the wall.

TL;DR: A Quadtree-based adaptive Cartesian/Quad (quadrilateral) grid generator, grid adaptor and flow solver have been developed and fully demonstrated to achieve maximum efficiency and accuracy with minimum human and computer resources.

TL;DR: In this paper, a new scheme called AUSMPW (AUSM by pressure-based weight functions) improved from the previous AUSM schemes by introducing the pressure based weight functions was proposed.

TL;DR: In this article, a deterministic forcing scheme for direct numerical simulation is developed which uses wave number-dependent linear amplification of the lower-wave number modes, relaxing them over time toward a model energy spectrum function, which accurately represents grid turbulence.

TL;DR: In this paper, a finite-volume method is developed for solving the convection-diffusion equation governing the transport of an insoluble surfactant over a generally evolving fluid interface, using an unstructured triangular grid.

TL;DR: In this article, an approximate Riemann solver is constructed for solving one class of two-phase models, where the flow behavior perpendicular to the tube axis is averaged, so that the model is essentially one-dimensional in the direction of the axis.

TL;DR: In this article, a numerical simulation has been performed with the nonlinear turbulence model proposed by Speziale (1987) on non-linear k-l and k-e models of turbulence, coupled with the K- e equations coming from the renormalization group theory (RNG) derived by Yakhot et al. The results are compared with the DNS data and measurements.

TL;DR: In this paper, the unsteady flow of blood in a straight, long, rigid pipe, driven by an oscillatory pressure gradient, was studied and three different non-Newtonian models for blood were considered and compared.

TL;DR: In this paper, a monotonic upwind conservation law based on the classical MUSCL construction and non-linear interpolation limiters is proposed for scalar hyperbolic conservation laws.

TL;DR: In this article, a three-dimensional multi-field coupled phasic exchange (CPE) algorithm is presented for the prediction of general two-phase flows, which is applicable to an arbitrary number of fields, a four-field construct is adopted here.

TL;DR: An efficient CFD approach based on higher order accurate numerical schemes has been developed for simulating unsteady hypersonic viscous flows strongly associated with shock-shock interference flow phenomena.

TL;DR: In this paper, the effect of surface waviness on boundary-layer transition in two-dimensional subsonic flow is investigated and the mean flow is calculated using an interacting boundary layer procedure, thereby accounting for viscous-inviscid interaction.

TL;DR: In this paper, a simple change of dependent variables for turbulence quantities is presented, which preserves positivity of all turbulence variables and leads naturally to a simple algorithm applicable to all two-equation models of turbulence.

TL;DR: In this paper, the incompressible two-dimensional Navier-Stokes equation was solved using a third-order upwind scheme, and a detailed error analysis was made before choosing a grid that minimises numerical dispersion and dissipation which are known to affect the higher order schemes.

TL;DR: In this paper, a three-dimensional numerical study was conducted to broaden our knowledge of the conjugate heat transfer in a finned-tube heat exchanger element, where a finite volume discretization method and a SIMPLE-based solution algorithm were applied to working differential equations and their discrete counterparts for computation of gas velocities and temperatures.

TL;DR: In this paper, a numerical optimization technique was developed to determine the optimum propeller blade shape for efficiency improvement, which satisfies the constraints of the constant power coefficient and the activity factor.

TL;DR: In this article, a simple and robust algorithm for steady inviscid flow, in terms of the primitive variables, is described for body fitted coordinates, adapted for the chimera framework for the calculation of flow past complex geometries.

TL;DR: In this article, the authors used a finite volume scheme and a two-equation turbulence model to simulate compressible and turbulent air-air coaxial jets with a strong velocity ratio.

TL;DR: In this article, a full fluid-structural coupled model was established to predict pressure fluctuation and pipe dynamic responses in a hydraulic power system, including the coupled effects of fluid flow and structural stiffness and damping.

TL;DR: In this paper, a review of the wide range of numerical methods available for modelling contaminant transport in rivers and estuaries is carried out, and theoretical considerations indicate that Eulerian-Lagrangian methods (ELMs), particularly the Lagrange-Galerkin method, show the most promise for these problems.

TL;DR: In this article, the effects of various gasdynamic phenomena on the attenuation of an electromagnetic (EM) wave propagating through the hypervelocity flow field generated by an aerodynamic body, are numerically investigated.

TL;DR: In this article, the effects of the dimensionless surface tension coefficient, the Reynolds number, the density ratio and the kinematic viscosity ratio on energy dissipation and wave profiles are investigated.

TL;DR: In this paper, a finite spectral method for pointwise or cellwise local spectral schemes based on non-periodic Fourier transform and two finite spectral schemes are presented. But this method is not suitable for wave propagation problems.

TL;DR: In this article, the focusing of a toroidal shock wave emitted from a coaxial annular shock tube and the resulting shock wave reflection were studied numerically with a dispersion-controlled scheme.

TL;DR: In this article, a numerical study of flow in a sinusoidally varying, periodic converging-diverging channel is performed to examine turbulent flow and heat transfer characteristics, based on the fully conserved control-volume representation of fully elliptic Navier-Stokes, and energy equations in body-fitted orthogonal curvilinear coordinate system.

TL;DR: In this article, the authors deal with the three-dimensional numerical simulation of the steady flow regimes in a fluid cell subjected to periodic accelerations with a relatively high frequency, focusing on the time averaged convective motion arising from thermovibrational effects, because of nonlinear coupling between density and acceleration oscillations.

TL;DR: In this paper, the Navier-Stokes equations were applied to the two-dimensional, unsteady, leading-edge flow over stationary, pitching and oscillating airfoils for flow past a parabola.