Mitigating water surface discontinuities in shallow water SPH flow model for flooding: Addressing discontinuities in particle mass distribution

In this paper, an approach is presented to mitigate the effects of water surface shock in shallow water Smoothed Particle Hydrodynamics (SPH) flow model which is commonly used for flash flood simulation. The proposed method involves the use of SPH interpolation techniques to calculate new mass values for individual fluid particles. Furthermore, adjustments are made to particle area and smoothing length parameters based on these interpolated values. Thorough testing of this method is conducted using a wet bed dam break test case, with comparisons made against both the standard shallow water SPH model and analytical solutions. The results demonstrate significant reductions in discontinuities within water depth and velocity, leading to improved overall simulation accuracy while preserving total mass conservation. This study makes a valuable contribution by addressing discontinuities in mass distribution within SPH flow modelling specifically applied to shallow water flows.