Showing papers in "Computers & Fluids in 2001"

TL;DR: In this article, a similarity solution to the Riemann problem of the one dimensional shallow water equations with a bottom step discontinuity is presented, which combines the basic theory of hyperbolic systems of conservation laws together with a sound interpretation of the physical concepts embedded in the shallow water system.

TL;DR: In this paper, statistically steady turbulent flow in straight, curved and helically coiled pipes is studied by means of direct numerical simulation to show the influence of curvature and torsion on turbulent flow.

TL;DR: An accurate, fast, matrix-free implicit method has been developed to solve the three-dimensional compressible unsteady flows on unstructured grids and indicates that the use of this method leads to a significant increase in performance over its explicit counterpart, while maintaining a similar memory requirement.

TL;DR: In this article, the authors applied the methodology developed in Part I [Comp. Fluids (2000), submitted for publication] to study underwater shock refracting at a gas-water interface.

TL;DR: The cell boundary element method (cell BEM) was also used to solve flows around two cylinders of equal diameter side by side and in tandem in this article, but no modifications to the method were needed to compute the flow field for these connected domains.

TL;DR: In this article, a finite-volume scheme of second-order accuracy and a semi-implicit time integration scheme of the same order of accuracy are used to integrate the incompressible Navier-Stokes equations on staggered grids.

TL;DR: In this article, a pseudospectral method is proposed for the computation of the three-dimensional Navier-Stokes equations inside a rotating cavity, which uses a second-order semi-implicit scheme for the time integration and a projection scheme to maintain the incompressibility constraint.

TL;DR: In this paper, Liu et al. developed a technique to simulate the flow field near a moving material interface for multi-material compressible flow, in particular for compressible gas-water flow.

TL;DR: In this article, the authors discuss recent achievements of direct numerical simulation (DNS) of incompressible flows and discuss various spatial discretization techniques which can be used in the case of simple or complex geometry.

TL;DR: In this article, a two-dimensional direct simulation Monte Carlo program for pressure boundaries using unstructured cells and its applications to typical micro-scale gas flows are described, including micro-manifold, micro-nozzle and slider air bearing.

TL;DR: The overset unstructured grid method developed for multiple-body problems is applied to a flow simulation about an experimental supersonic airplane separation from a rocket booster and clearly simulates the complex reflection patterns of shock waves between two bodies during the separation process.

TL;DR: A high-order accurate scheme is constructed for the Euler equations thanks to suitably weighted discretization operators and the influence of mesh deformations on the scheme accuracy is studied theoretically and numerically.

TL;DR: In this article, a fractional step method for the solution of Navier-Stokes equations is proposed, which is based on a finite-volume formulation and uses the pressure in the cell center and the mass fluxes across the faces of each cell as dependent variables.

TL;DR: A generalized treatment of approximate factorization schemes is given, based on an operator notation for the spatial approximation of Euler and Navier–Stokes algorithms as nonlinear systems of partial differential equations, to unify a large number of schemes developed over the past 30 years.

TL;DR: In this paper, a mapping approach is proposed for the numerical simulation of distributive mixing in three-dimensional laminar flows, based on a spatial discretization of the locally averaged concentration of fluid components in the mixture (the so-called coarse grain density).

TL;DR: In this article, three methods for simulation of flows over corrugated/rough boundaries have been analyzed and the effectiveness of these methods has been evaluated: direct, domain perturbation and domain transformation methods.

TL;DR: In this article, a new numerical scheme for solution of pure advection process has been proposed, which is based on backward characteristics method and it employs cubic spline interpolation method to interpolate the dependent variable at the foot of concentration characteristic in the time-line.

TL;DR: In this article, a discrete vortex method was used to simulate the situation of flow past a rotating circular cylinder, and the effects of the oscillating amplitude and frequency on the forces acting on the cylinder were determined together with the flow pattern in the wake.

TL;DR: In this article, the effect of the endwall fences on the secondary flow in the turbine cascade with and without an endwall fence is investigated. But the authors focus on the effects of the fence height on secondary flow control.

TL;DR: Stability and convergence studies reveal that the ADI and DDLGS schemes possess attractive convergence properties at all aspect ratios for 2D problems, while the DDADI andDDLU schemes perform worse at high aspect ratios.

TL;DR: In this paper, a new computational approach called fully coupled procedure with defect correction technique is presented as an alternative both to classical decoupled approaches (SIMPLE [Int. J. Heat Mass Transfer 15 (1972) 1787-1806], PISO [J. Comput. Phys. 62(1) (1986) 40−65] and variants) and to weakly coupled solution methods of Vanka type.

TL;DR: An implicit procedure for minimizing the error introduced by approximate factorization in solving scalar or block multidiagonal matrix equations is presented with applications to fluid dynamics.

TL;DR: In this paper, an implicit, multigrid scheme has been extended to treat unsteady flows using the concept of temporal subiteration (or dual-time stepping, as it sometimes is called).

TL;DR: In this paper, a specially combined lower-upper factored implicit scheme based on the lower upper symmetric-Gauss-Seidel (LU-SGS) implicit scheme in conjunction with diagonalization and Gaussian elimination (GE) is proposed for solving the compressible, three-dimensional Navier-Stokes equations and the two-equation q − ω turbulence model.

TL;DR: In this article, a driven cavity is used as a test case to test the suitability of pseudo-compressibility algorithm for mixed convection flow problems for both laminar and turbulent flow situations.

TL;DR: In this paper, a numerical method is developed for simulating the surface tension induced three-dimensional oscillations of inviscid liquid drops suspended in a dynamically inert (inviscid and zero density) ambient fluid.

TL;DR: In this article, the effects of various pressure gradients on developing symmetric wakes and on the ability of a linear eddy viscosity model and a nonlinear explicit algebraic stress model to accurately predict their downstream evolution were investigated.

TL;DR: In this paper, a direct numerical simulation of an equilibrium turbulent pipe flow at a Reynolds number of 2500, based on bulk velocity and pipe diameter, was carried out with a grid of about 7.4×10 5 points and a fully resolved wall layer.

TL;DR: In this paper, a group of high-order finite-difference schemes for incompressible flow was implemented to simulate the evolution of turbulent spots in channel flows, and the long-time accuracy of these schemes was tested by comparing their evolution of small disturbances to a plane channel flow against the growth rate predicted by linear theory.

TL;DR: In this article, the authors describe the extension of least squares kinetic upwind method for moving grids (LSKUM-MG), which is a kinetic theory based upwind Euler solver.