ISSN:0044-2267    

DOI:10.1002/zamm.19970770802

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractIn this paper the volume fraction concept in the porous media theory is considered. First, the historical development of this important concept is traced. Thereupon, the concept of volume fractions is formulated and the transport theorems, which govern the transformations of volume elements from one placement to another, are derived. An essential feature is the incorporation of the effect of incompressibility into the transport theorems. This is only possible by the introduction of a new multiplicative decomposition of the deformation gradients of the constituents into parts describing the deformations of the realistic (true) materials and parts including the changes of the pores.

ISSN:0044-2267    

DOI:10.1002/zamm.19970770803

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19970770804

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractAn effective approach to solving the problem of steady flow of incompressible nonlinear viscous fluid in arbitrary axisymmetric channels is introduced. We show how to reduce the problem to a variational one, and then how to find the saddle point of an appropriate functional. The relevant techniques are pointed out. We analyse some numerical results.

ISSN:0044-2267    

DOI:10.1002/zamm.19970770807

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19970770810

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractIn der vorliegenden Arbeit wird das Problem der Finite‐Elemente‐Analyse gummiartiger, strikt inkompressibler Elastomere unter großen Verzerrungen und Kontaktwechselwirkungen behandelt. Die Inkompressibilitätsbedingungen werden durch Ausschließung in expliziter Form eines Teiles von Komponenten des Verschiebungsfeldes aus dem globalen FE‐Gleichungssystem erfüllt. Numerische Aspekte dieser Vorgehensweise werden ausführlich besprochen. Zur Modellierung der reibungslosen Kontaktwechselwirkung von Oberflächen eines modellierten Körpers miteinander und mit festen Anschlägen wird die Penalty‐Methode angewandt. Numerische Beispiele und experimentelle Ergebnisse werden angeführ

ISSN:0044-2267    

DOI:10.1002/zamm.19970770811

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractIn three‐dimensional space there are seven series of classes, i,e.,

ISSN:0044-2267    

DOI:10.1002/zamm.19970770812

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractMany different methods have been suggested for the numerical solution of index 2 and 3 Euler‐Lagrange equations. We focus on 0‐stability of multistep methods (φ, σ) and investigate the relations between some well‐known computational techniques. By various modifications, referred to as β‐blocking of the σ polynomial, some basic shortcomings of multistep methods may be overcome. This approach is related to projection techniques and has a clear and well‐known analogy in control theory. In particular, it is not necessary to use BDF methods for the solution of high index problems; indeed, “nonstiff” methods may be used for part of the system provided that the state‐space form is nonstiff. We illustrate the techniques and demonstrate the results with a simplified multibo

ISSN:0044-2267    

DOI:10.1002/zamm.19970770813

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

ISSN:0044-2267    

DOI:10.1002/zamm.19970770816

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY

摘要:

AbstractWe consider the eigenvalue problem of the Stokes operator in a bounded cylindrical domain of ℝ3with homogeneous Dirichlet boundary conditions on the curved part of the boundary and periodical conditions in the main stream direction. We deduce by separation the corresponding systems of ordinary differential equations and solve them explicitly looking for bounded, solenoidal vector fields fulfilling the boundary conditions. The investigation of possible cases yields either the explicit eigenfunctions and eigenvalues, or equations for the determination of the eigenvalues, and a general representation of the eigenfunction

ISSN:0044-2267    

DOI:10.1002/zamm.19970770817

出版商:WILEY‐VCH Verlag    

年代:1997

数据来源: WILEY