Non-conforming Interface Conditions for the Second-Order Wave Equation

Abstract Imposition methods of interface conditions for the second-order wave equation with non-conforming grids is considered. The spatial discretization based on high order finite differences summation-by-parts properties. Previously presented solution this problem, simultaneous approximation term (SAT) method, have shown to introduce significant stiffness. This can lead highly inefficient schemes. Here, two new imposing avoid stiffness problems are presented: (1) a projection method and (2) hybrid between SAT method. Numerical experiments performed using traditional order-preserving interpolation operators. Both novel retain accuracy convergence behavior previously developed but significantly less stiff.