ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

On the mechanical inconsistency of symmetrization of unsymmetric coupling matrices for BEFEM discretizations of solids (1989)

Mang, H. A. ; Torzicky, P. ; Chen, Z. Y.

Springer

Computational mechanics 4 (1989), S. 301-308

add to mindlist on the mindlist

Details

ISSN: 1432-0924

Source: Springer Online Journal Archives 1860-2000

Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Notes: Abstract For several technical problems discretization of the boundary of a part of a solid by the BEM and of the remaining part of the solid by the FEM is useful in order to exploit the complementary advantages of the BEM and of the FEM optimally. A characteristic feature of the employed “local FEM approach” for the coupling of such discretizations are “coupling matrices” representing load-stiffness matrices which are associated with displacement-dependent node forces acting on the interface of the two parts of the solid. Because of the nature of the employed BEM these matrices are unsymmetric. It is proved theoretically that symmetrization of such coupling matrices is mechanically inconsistent. It is also demonstrated that this symmetrization may lead to a significant deterioration of the quality of numerical results.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00301388

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Discrete orthogonalization of parameter lines on curved surfaces for finite element analysis of thin shells (1985)

Eberhardsteiner, J. ; Mang, H. A.

Chichester [u.a.] : Wiley-Blackwell

International Journal for Numerical Methods in Engineering 21 (1985), S. 837-851

add to mindlist on the mindlist

Details

ISSN: 0029-5981

Keywords: Engineering ; Engineering General

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Mathematics , Technology

Notes: Orthogonal curvilinear co-ordinates represent the logical choice for description of the middle surface of the majority of shells in engineering practice. By means of orthogonalization of originally skew parameter lines at integration points for shell analysis by the finite element method (FEM), the remaining minority can be treated without having to resort to skew curvilinear co-ordinates. Therefore, it does not seem to be worth while to extend existing computer codes for shell analysis by the FEM, restricted to orthogonal curvilinear co-ordinates, to general curvilinear co-ordinates. Depending on the structure of such a code, this extension may require a substantial amount of recoding. (However, it is advisable to consider general curvilinear co-ordinates if a new computer code for shell analysis by the FEM, based on thin- or thick-shell theory, is written).Based on these considerations, the concept of ‘discrete orthogonalization of parameter lines’ has been developed. It is presented in this paper and applied to the analysis of a hyperbolic paraboloid groined vault subjected to dead load. In the numerical investigation it is demonstrated that treating skew parameter lines incorrectly as orthogonal has a significant effect on the results for the displacements and the internal forces.

Additional Material: 13 Ill.