摘要:

AbstractThis paper presents a survey of several finite difference schemes for the steady‐state convection–diffusion equation in one and two dimensions. Most difference schemes have O(h2) truncation error. The behaviour of these schemes on a one‐dimensional model problem is analysed in detail, especially for the case when convection dominates diffusion. It is concluded that none of these schemes is universally second order. One recently proposed scheme is found to yield highly inaccurate solutions for the case of practical interest, i.e. when convection dominates diffusion. Extensions to two and threedimensions are also disc

ISSN:0271-2091    

DOI:10.1002/fld.1650030403

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThe shallow‐water equations in radial symmetry are solved numerically to simulate the collapse of a cylindrical liquid column into an area surrounded by a concentric dike. The following three subcases of this problem are considered: a liquid column collapsing onto a layer of the same liquid, a liquid column collapsing onto a solid surface, and a column of lighter liquid collapsing onto a heavier liquid (i.e. liquefied natural gas (LNG) spilled onto water). The results for the three categories are compared and the differences and similarities between them are analyse

ISSN:0271-2091    

DOI:10.1002/fld.1650030404

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractA simple numerical model based on the shallow water equations in radial symmetry is used to simulate both instantaneous and continuous spills of liquefied natural gas (LNG) onto a water surface. Using the computed results, a study is made of the similarities and differences in the pool structure resulting from the two types of spills. For instantaneous spills a relation linear on a logarithmic plot is suggested between the maximum pool size and the spill volume. The effects of shear forces and surface cohesivity on the evolution of the spill are also examined.

ISSN:0271-2091    

DOI:10.1002/fld.1650030405

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractHeat transfer associated with forced convection between bundles of cylindrical fuel rods is analysed using the finite element method. A subchannel technique is employed and the numerical results are compared with previous experimental and numerical values. The solid and fluid zones are analysed, for temperature distribution, as a single domain.

ISSN:0271-2091    

DOI:10.1002/fld.1650030406

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractA formulation of a mixed finite element method for the analysis of unsteady, convective, incompressible viscous flow is presented in which: (i) the deviatoric‐stress, pressure, and velocity are discretized in each element, (ii) the deviatoric stress and pressure are subject to the constraint of the homogeneous momentum balance condition in each element,a priori, (iii) the convective acceleration is treated by the conventional Galerkin approach, (iv) the finite element system of equations involves only the constant term of the pressure field (which can otherwise be an arbitrary polynomial) in each element, in addition to the nodal velocities, and (v) all integrations are performed by the necessary order quadrature rules. A fundamental analysis of the stability of the numerical scheme is presented. The method is easily applicable to 3‐dimensional problems. However, solutions to several problems of 2‐dimensional Navier‐Stokes' flow, and their comparisons with available solutions in terms of accuracy and efficiency, are discussed in detail in Part II of thi

ISSN:0271-2091    

DOI:10.1002/fld.1650030407

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

摘要:

AbstractThis paper investigates the problems involved in the numerical simulation of free surface wave motions and surface wave effects on marine structures. Various approaches that might be taken in meeting these problems are discussed, and their relative advantages and disadvantages are considered. One particular approach combines a Lagrangian formulation of the governing equations, a triangular grid and a finite‐difference solution procedure. Since this approach has some distinct advantages in the numerical calculation of fluid flows which include a free surface, it formed the basis for the development of one particular computer code, SPLISH. Sufficient progress has been made with the SPLISH code to demonstrate the attractiveness of numerical calculations for wave flow problems. Recent computational results demonstrate that realistic time‐varying local flow fields, pressures and forces on and near structures such as a half‐cyclinder on the ocean floor can be determined from numerical calculations for certain conditions. Good agreement is found in comparison of the numerical results from SPLISH, recent linear wave Green's function and fifth‐order asymptotic solutions for wave motion over a bottom seated half‐cylinder, and an experimental simulation in a wav

ISSN:0271-2091    

DOI:10.1002/fld.1650030408

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

ISSN:0271-2091    

DOI:10.1002/fld.1650030409

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY

ISSN:0271-2091    

DOI:10.1002/fld.1650030402

出版商:John Wiley&Sons, Ltd    

年代:1983

数据来源: WILEY