摘要:

AbstractIn this paper we consider an incompressible version of the two‐fluid network model proposed by Porsching (Nu. Methods Part. Diff. Eq.,1, 295–313 [1985]). The system of equations governing the model is a mixed system of differential and algebraic equations (DAEs). These DAEs are then recast, through proper transformation, into a system of ordinary differential equations on a submanifold of ℝn, for which uniqueness, existence, and stability theorems are proved. Numerical simulations are pres

ISSN:0749-159X    

DOI:10.1002/num.1690050102

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY

摘要:

AbstractIn this paper we study a widely used zero equation model of turbulence. The governing equations are derived by applying to the incompressible Navier‐Stokes equations the Reynolds time averaging procedure. We achieve closure by employing the eddy viscosity concept. Using the Implicit Function Theorem we obtain an existence and uniquencess result. We also discuss the existence of nonsingular solutions. Finally, we present an algorithm for solving the modeled equation

ISSN:0749-159X    

DOI:10.1002/num.1690050103

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY

摘要:

AbstractSpectral techniques for solving problems in non‐Newtonian fluid mechanics are introduced. Following the work of Coleman (J. Non‐Newtonian Fluid Mech.;15, 227–238 [1984]), the governing equations for the creeping flow of a co‐rotational Maxwell fluid are written in terms of the Airy stress function and a stream function. This ensures that the continuity and momentum equations are automatically satisfied. The choice of trial functions for solving a one‐dimensional model problem using spectral methods is discussed. Methods for treating unbounded domains and accurately representing reentrant boundary singularities within the spectral context are also c

ISSN:0749-159X    

DOI:10.1002/num.1690050104

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY

摘要:

AbstractThis paper presents an experimental performance analysis for the rate of convergence ofcollocationon general domains using a bicubic Hermite basis. Twenty domains are selected for the experiment from the population of PDEs on nonrectangular domains found inRealistic PDE Solutions for Non‐rectangular Domains(C. J. Ribbens and J. R. Rice, CSD‐TR 639, Department of Computer Sciences, Purdue University, 1986), including one rectangle for comparison. The result shows that the convergence of the ELLPACK module COLLOCATION behaves asO(h4) on all 19 of the nonrectangular domains. This set includes a large variety of nonrectangular domains (only two have reentrant corners). We conclude that, with very high probability, this collocation module hasO(h4) convergence on general domains.The experiment is made by using the Performance Evaluation System (PES) of ELLPACK, which includes the population of PDEs on nonrectangular domains. Several performance analysis tools are used to analyze the rate of convergence, the most informative is a visual examination of the convergence behav

ISSN:0749-159X    

DOI:10.1002/num.1690050105

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY

ISSN:0749-159X    

DOI:10.1002/num.1690050106

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY

ISSN:0749-159X    

DOI:10.1002/num.1690050107

出版商:John Wiley&Sons, Inc.    

年代:1989

数据来源: WILEY