عنوان

A Projection Transformation Method for Nearly Singular Surface Boundary Element Integrals

(Number (ISBN

364284698X

(Number (ISBN

9783642846984

Number

b574582

Title Proper

A Projection Transformation Method for Nearly Singular Surface Boundary Element Integrals

General Material Designation

[Book]

First Statement of Responsibility

by Ken Hayami.

Place of Publication, Distribution, etc.

Berlin, Heidelberg

Name of Publisher, Distributor, etc.

Springer Berlin Heidelberg

Date of Publication, Distribution, etc.

1992

Specific Material Designation and Extent of Item

(x, 456 Seiten)

Series Title

Lecture Notes in Engineering, 73

Text of Note

In three dimensional boundary element analysis, computation of integrals is an important aspect since it governs the accuracy of the analysis and also because it usually takes the major part of the CPU time. The integrals which determine the influence matrices, the internal field and its gradients contain (nearly) singular kernels of order lIr a (0:= 1,2,3,4,.··) where r is the distance between the source point and the integration point on the boundary element. For planar elements, analytical integration may be possible 1,2,6. However, it is becoming increasingly important in practical boundary element codes to use curved elements, such as the isoparametric elements, to model general curved surfaces. Since analytical integration is not possible for general isoparametric curved elements, one has to rely on numerical integration. When the distance d between the source point and the element over which the integration is performed is sufficiently large compared to the element size (d> 1), the standard Gauss-Legendre quadrature formula 1,3 works efficiently. However, when the source is actually on the element (d=O), the kernel 1I~ becomes singular and the straight forward application of the Gauss-Legendre quadrature formula breaks down. These integrals will be called singular integrals. Singular integrals occur when calculating the diagonals of the influence matrices.

Appl. Mathematics/Computational Methods of Engineering.

Integral Equations.

Mathematics.

Class number

Book number

by Ken Hayami.

Ken Hayami

Electronic name

[Book]

Y