Structure-preserving integrators for dissipative systems based on reversible-irreversible splitting (Shang Xiaocheng, ETH Zurich)
20.11.2018 14:00
We study the optimal design of numerical integrators for dissipative systems, for which there exists an underlying thermodynamic structure known as GENERIC (General Equation for the NonEquilibrium Reversible-Irreversible Coupling). We present a framework to construct structure-preserving integrators for linearly damped systems by splitting the system into reversible and irreversible parts. The reversible part, which is typically a Hamiltonian system, is solved by using a symplectic method (e.g., Verlet), for which an associated modified Hamiltonian in the form of a series expansion can be obtained by using backward error analysis. The modified Hamiltonian is then used to adjust the irreversible part in such a way that the modified total energy for the whole system can be conserved. Our findings are verified by various numerical experiments, demonstrating the superiority of structure-preserving integrators over alternative schemes in terms of the accuracy control of both energy conservation and entropy production as well as the preservation of the dissipation rate.
Lieu
salle 623, Séminaire d'analyse numérique
Organisé par
Section de mathématiquesIntervenant-e-s
Shang Xiaocheng, ETH Zurich, Polymer Physicsentrée libre