Table 1 Measured iteration numbers n for the stand-alone solver and \(n_{CG}\) for the preconditioned CG method attained for the model problem (19) on the configuration depicted in Fig. 1 using a single element overlap
From: Multilevel preconditioners for embedded enriched partition of unity approximations
\(\varvec{k}\) | \({{\mathbf {{\small {\uppercase {Dof}}}}}}\) | \(\varvec{n_\mathrm {V(1,1)}}\) | \(\varvec{n_\mathrm {V(3,3)}}\) | \(\varvec{n_\mathrm {W(1,1)}}\) | \(\varvec{n_\mathrm {CGV(1,1)}}\) | \(\varvec{n_\mathrm {CGV(3,3)}}\) | \(\varvec{n_\mathrm {CGW(1,1)}}\) |
|---|---|---|---|---|---|---|---|
3 | 1479 | 23 | 9 | 23 | 12 | 7 | 12 |
4 | 5386 | 22 | 11 | 22 | 12 | 8 | 12 |
5 | 20,249 | 19 | 12 | 19 | 12 | 9 | 11 |
6 | 79,681 | 22 | 15 | 18 | 12 | 10 | 11 |
7 | 315,046 | 26 | 16 | 17 | 14 | 11 | 11 |
8 | 1,245,303 | 38 | 22 | 18 | 17 | 12 | 11 |
9 | 4,958,241 | 43 | 22 | 18 | 18 | 12 | 11 |