Zienkiewicz O.C., Taylor R.L. Vol. 3. The finite - tiera.ru

4
8.9.3 DtN mapping
2
Fig. 8.6 Continued.
2
2
6 2
4
10 2 6 2
6
6 2
6
2
2
2 18
9
2
6 6
6 6
10
2 4
2
The approach described above has been re-invented by recent authors and given the
title Dirichlet to Neumann (DtN) mapping. See a comparison by Astley. 39 A detailed
survey of this approach, which goes beyond the wave equation, is given by Givoli. 29
8.10 In®nite elements
2
2
2
2
2
2
2
2
2
2 2
In®nite elements are described in the book by Bettess, 40 which although somewhat
out-of-date, still gives a useful introduction to the topic. More recent reviews are
by Astley, 41 and Gerdes. 42 The methods described in Volume 1, Chapter 9, can be
developed to include periodic e€ects. This was ®rst done by Bettess and Zienkiewicz,
using so-called `decay function' procedures and they were very e€ective. 11;18 Comparison
results with Chen and Mei 36;37 for the arti®cial island problem are shown in
2
6 12
5
2
(b) Contours of wave height amplification, grid 3. 232-s wave period
2
4
2
2
2
5
In®nite elements 259