Transient $L^1$ error estimates for well-balanced schemes on non-resonant scalar balance laws

Debora Amadori (1) , Laurent Gosse (2)

1 DISIM - Department of Information Engineering, Computer Science and Mathematics = Dipartimento di Ingegneria e Scienze dell'Informazione e Matematica [L'Aquila]
2 IAC - Istituto per le Applicazioni del Calcolo "Mauro Picone"

The ability of Well-Balanced (WB) schemes to capture very accurately steady-state regimes of non-resonant hyperbolic systems of balance laws has been thoroughly illustrated since its introduction by Greenberg and LeRoux \cite{grl} (see also the anterior WB Glimm scheme in \cite{we}). This paper aims at showing, by means of rigorous $C^0_t(L^1_x)$ estimates, that these schemes deliver an increased accuracy in transient regimes too. Namely, after explaining that for the vast majority of non-resonant scalar balance laws, the $C^0_t(L^1_x)$ error of conventional fractional-step \cite{tt2} numerical approximations grows {\bf exponentially} in time like $\exp(\max(g')t)\sqrt{ \DX}$ (as a consequence of the use of Gronwall's lemma), it is shown that WB schemes involving an exact Riemann solver suffer from a much smaller error amplification: thanks to strict hyperbolicity, their error grows at most only {\bf linearly} in time. Numerical results on several test-cases of increasing difficulty (including the classical LeVeque-Yee's benchmark problem \cite{ly} in the non-stiff case) confirm the analysis.

Mots clés: error estimates; Well-balanced Godunov scheme; Wave-front tracking algorithm; functional equivalent to the $L^1$ distance; numerical viscosity; non-linear resonance; Gronwall lemma; error estimates.

Domaines: Analyse numérique [math.NA]

Debora Amadori, Laurent Gosse. Transient $L^1$ error estimates for well-balanced schemes on non-resonant scalar balance laws. Journal of Differential Equations, 2013, pp.469-502. ⟨10.1016/j.jde.2013.04.016⟩. ⟨hal-00781393v2⟩