Partial Differential Equations - Modelling and ... - ResearchGate
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Table 1. Primal DG for transport<br />
Discontinuous Galerkin Methods 23<br />
OBB-DG NIPG SIPG IIPG<br />
Penalty Term 0 ≥ 0 >σ 0 > 0 > 0 <strong>and</strong> ≪ σ 0<br />
Optimality in L 2 (H 1 )orH 1 Yes Yes Yes Yes<br />
Optimality in L 2 (L 2 )orL 2 No No Yes No<br />
Robust probs. with highly var. coeffs. Yes Yes No Yes<br />
Scalar primary interest(transp.) No No Yes No<br />
Compatibility Flow Condition No No No Yes<br />
coefficients <strong>and</strong> for transport problems in which the scalar variable is of primary<br />
interest. These results were obtained from an extensive set of numerical<br />
experiments. The studies indicate that the non-symmetric DG formulations<br />
are more robust in h<strong>and</strong>ling rough coefficients. The symmetric form performs<br />
better for treating diffusion/advection/reaction problems since the SIPG form<br />
yield optimal L 2 <strong>and</strong> non-negative norm estimates. The last row summarizes<br />
a compatibility condition formulated in [DSW04] in which the objective is to<br />
choose a flow field that preserves positive concentrations in reactive transport.<br />
The IIPG method is the only primal DG for which this holds.<br />
DG methods are currently being investigated for modeling multiphase flow<br />
in porous media, e.g., see [BR04, KR06] for two-phase incompressible <strong>and</strong> for<br />
two <strong>and</strong> three phases compressible systems see [HF06, Esl05, SW]. While<br />
much progress has been made in modeling transport a major disadvantage for<br />
DG has been the development of efficient parallel solvers for large linear <strong>and</strong><br />
nonlinear systems, the pressure equation or a fully implicit formulation for<br />
multiphase flow respectively. The development of DG solvers is an active area<br />
of research <strong>and</strong> new domain decomposition approaches are currently being<br />
developed, e.g., see [Kan05, Joh05, AA07, Esl05, BR00].<br />
References<br />
[AA07]<br />
[ABCM02]<br />
[Arn79]<br />
[Arn82]<br />
[Bab73]<br />
P. F. Antonietti <strong>and</strong> B. Ayuso. Schwarz domain decomposition preconditioners<br />
for discontinuous Galerkin approximations of elliptic problems:<br />
non-overlapping case. M2AN Math. Model. Numer. Anal., 41(1):21–54,<br />
2007.<br />
D. N. Arnold, F. Brezzi, B. Cockburn, <strong>and</strong> L. D. Marini. Unified analysis<br />
of discontinuous Galerkin methods for elliptic problems. SIAM J.<br />
Numer. Anal., 39(5):1749–1779, 2002.<br />
D. N. Arnold. An interior penalty finite element method with discontinuous<br />
elements. PhD thesis, University of Chicago, Chicago, IL, 1979.<br />
D. N. Arnold. An interior penalty finite element method with discontinuous<br />
elements. SIAM J. Numer. Anal., 19(4):742–760, 1982.<br />
I. Babu˘ska. The finite element method with Lagrangian multipliers.<br />
Numer. Math., 20:179–192, 1973.