Solitary wave generation using moving boundary in shallow water SPH flow model

Solitary waves have been widely used by researchers to represent tsunami waves in a physical experiment, although this assumption is still being debated. The most common way to generate a solitary wave in the hydraulics laboratory is by using a horizontal movement of a vertical board, or one can also name it the piston-type wave-maker. This paper investigates the performance of the depth-averaged Smoothed Particle Hydrodynamics (SPH) flow model, which utilises a Lagrangian scheme and is capable of imposing moving solid boundaries, to reproduce the analytical solitary wave solution. The numerical result demonstrates the capability of the moving boundary to reproduce the solitary wave by imposing the displacement time history of the paddle according to the theoretical solution. The wave shape, however, is changing and finally steepening as it propagates due to the dissipative effect and the hydrostatic pressure assumption in the formulation derivation, a common problem in depth-averaged flow models. Enhancing the formulation for achieving a dispersion-free flow model will enhance the software's capability to serve as a reliable tool for simulating solitary or general waves in coastal engineering research, whether at real-world or laboratory scales, without being constrained by the specifications of the wave-maker machine.