摘要:

The aerodynamic characteristics of tandem cables of cable-stayed bridges have become an increasingly serious problem with increments in span length. In order to reduce the construction cost and maintenance of cables, tandem cables have been adopted for cable-stayed bridges. These cables, however, have aerodynamic response characteristics such as wake-galloping. Therefore, a method to suppress wake-galloping in tandem cables is required. The purpose of this study is to investigate the characteristics of the wake-galloping phenomenon of tandem cables of cable-stayed bridges using numerical fluid flow analysis. The flow around the oscillating tandem circular cylinders modeled on tandem cables is calculated. The flow field is treated as an incompressible viscous flow. The Arbitrary Lagrangian-Eulerian (ALE) method is employed to solve the flow field around the cylinders, and the three-step Taylor-Galerkin method, which is based on a fractional step finite element method, is adopted for discretization.

ISSN:1061-8562    

DOI:10.1080/10618569808940852

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Parallel implementation of the finite element method for the Helmholtz equation and the Stokes equations is discussed in the environment of a distributed-memory massively parallel computer where data is shared among the processors by communication procedures called message-passing. For implementation of the finite element methods based on domain decomposition, “pre-assembly type” and “restriction type” are introduced for data on nodal points. They simplify the implementation and reduce the amount of message-passing between subdomains. In order to reduce this further, the mortar element method is applied to the primitive variables of the Stokes equations. It maintains natural treatment of stress boundary conditions, which is an advantage of the finite element method. Its implementation can be described concisely by the idea of the two data types.

ISSN:1061-8562    

DOI:10.1080/10618569808940853

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Time-dependent analysis of rubber flow from a capillary rheometer is analyzed by the finite element method, in which both marker-particle and pseudo-concentration methods are used to define extruding rubber positions. The rubbers are assumed to be represented by a power-law fluid. The extruded free surface obtained by the marker-particle method is compared with the one produced by the pseudo-concentration method.

ISSN:1061-8562    

DOI:10.1080/10618569808940854

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The purpose of this paper is to develop a consistent method to calculate the fluxes or the stresses in an incompressible flow, particularly a turbulent flow. A post-processing technique has been developed such that fluxes or stresses are treated as unknown values, which are solved for, weakly, using the finite element method.

ISSN:1061-8562    

DOI:10.1080/10618569808940855

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

This paper highlights the finite element hydrodynamic and transport modeling developments being conducted by the U.S. Army Engineer Waterways Experiment Station (WES) and its partnering organizations. The WES developments in support of surface water, groundwater, and watershed management are presented. A particular facet of these developments, the creation of integrated, comprehensive modeling systems which greatly increase the productive use of WES hydroenvironmental models, is discussed. Future development directions, including the use of scalable high performance computing resources, are also provided.

ISSN:1061-8562    

DOI:10.1080/10618569808940856

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

We describe and demonstrate both our newest projection method (fully implicit) for the incompressible Navier-Stokes equations via the finite element method and our newest turbulence model - a somewhat sophisticated nonlinear (cubic) eddy viscosity model that does not employ wall functions or normal distances to walls - the combination providing a method and a model that is each applicable in arbitrary geometry. We demonstrate both via a flow simulation past an automobile-like body at a Reynolds number of 4.3 million.

ISSN:1061-8562    

DOI:10.1080/10618569808940857

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

In this paper, we present a new Galerkin finite element method with bubble function for the compressible Euler equations. This method is derived from thescaled bubble elementfor the advection-diffusion problems developed by Simo and his colleagues, which is based on the equivalence between the Galerkin method employing piecewise linear interpolation with bubble functions and the Streamline-Upwind/Petrov Galerkin (SUPG) finite element method using P1approximation in the steady advection-diffusion problem. Simo and this author have applied this approach to transient advection-diffusion problems by using a special scaled bubble function calledP-scaled bubble, which is designed to work in the transient advection-diffusion problems for any Peclet number from 0 to ∞. The method presented in this paper is an application of this p-scaled bubble element to a pure hyperbolic system.

ISSN:1061-8562    

DOI:10.1080/10618569808940858

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

A finite element formulation to solve the Ekman potential flow model for wind fields over complex terrain is presented. Appropriate combinations of the boundary conditions on the artificial boundary surfaces are investigated in the formulation. Numerical examples show that the computed wind fields exhibit the typical features of the wind velocity profile in the Ekman boundary layer. Influence of the terrain topography is also observed.

ISSN:1061-8562    

DOI:10.1080/10618569808940859

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The Modified Galerkin Method (MGM) has been proposed as one of the most efficient methods for two-dimensional convection-diffusion equations. In the MGM, the non-symmetric matrices, which are derived from the convection term in the Galerkin formulation, are not used, and an artificial diffusion is introduced through an error analysis approach to improve its discretization accuracy in both time and space directions. In this study, the MGM is applied for two-dimensional viscous fluid flow analysis, and the driven cavity flow problems are solved up to Reynolds number of 10,000 using the vorticity-stream function formulation and non-uniform meshes. The results show the effectiveness of MGM.

ISSN:1061-8562    

DOI:10.1080/10618569808940860

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

We present a computational method for drag coefficients of axisymmetric bodies. It is a kind of consistent flux method but the introduction of a proper test function enables us to establish an error estimate under some assumption. Applying the method, we obtain drag coefficients of a sphere for Reynolds numbers between 10 and 200, which are found between numerical upper and lower bounds.

ISSN:1061-8562    

DOI:10.1080/10618569808940861

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor