Error estimates for Galerkin approximations of the Serre equations
Provides rigorous error bounds and a practical numerical scheme for the Serre equations, which model long waves in ideal fluids, but the results are incremental as they extend known techniques to this specific system.
The authors prove optimal-order L2-error estimates for Galerkin finite element discretizations of the Serre equations and construct a highly accurate fully discrete scheme using Runge-Kutta time stepping, demonstrating its effectiveness in simulating solitary wave interactions.
We consider the Serre system of equations which is a nonlinear dispersive system that models two-way propagation of long waves of not necessarily small amplitude on the surface of an ideal fluid in a channel. We discretize in space the periodic initial-value problem for the system using the standard Galerkin finite element method with smooth splines on a uniform mesh and prove an optimal-order $L^{2}$-error estimate for the resulting semidiscrete approximation. Using the fourth-order accurate, explicit, `classical' Runge-Kutta scheme for time stepping we construct a highly accurate fully discrete scheme in order to approximate solutions of the system, in particular solitary-wave solutions, and study numerically phenomena such as the resolution of general initial profiles into sequences of solitary waves, and overtaking collisions of pairs of solitary waves propagating in the same direction with different speeds.