Releasing the Time Step Upper Bound of CFL Stability Condition for the Acoustic Wave Simulation With Model-Order Reduction

The maximum time step size for the explicit finite-difference scheme complies with Courant–Friedrichs–Lewy (CFL) stability condition, which essentially restricts optimization and tuning of communication-intensive massive seismic wave simulation in a parallel manner. This study brings forward model-order reduction (MOR) method to simulate acoustic propagation. It briefly takes advantage update matrix’s eigenvalues expansion coefficients variables semi-discrete equation, reducing computational complexity enhancing its computing efficiency. Moreover, we introduced eigenvalue abandonment perturbation methods stabilize unstable oscillations when breaks CFL upper bound. We then time-dispersion transform eliminate error caused by large secure high accuracy. Numerical experiments exhibit that MOR method, conjunction (and perturbation) can capture highly accurate waveforms even exceeds condition. is suitable strongly heterogenous media maintain numerical accuracy toward bound Nyquist sampling.