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

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it can be written as (see reference 22 for details)
h
e ˆ ÿ h ˆ ch 2 d 2
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Fig. 4.10 Flow past a backward facing step. Exercise on exit boundary conditions, Re ˆ 100.
dx2 ch 2 2 h
d
dx2 …4:21†
where
h
is the ®nite element solution and c is a constant.
If, for instance, we further assume that ˆ h at the nodes, i.e. that the nodal error
is zero, then e represents the values on a parabola with a curvature of d 2 h =dx 2 . This
allows c, the unknown constant, to be determined, giving for instance the maximum
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Fig. 4.11 Flow past a backward facing step. Solution with a longer domain, Re ˆ 100.
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Adaptive mesh re®nement 105
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