  Lagrangian particle-based methods have opened new perspectives for the
investigation of complex problems with large free-surface deformation. Some
well-known particle-based methods adopted to solve non-linear hydrodynamics
problems are the smoothed particle hydrodynamics (SPH) and the moving particle
semi-implicit (MPS). Both methods modeled the continuum by a system of
Lagrangian particles (points) but adopting distinct approaches for the
numerical operators, pressure calculation, and boundary conditions. Despite the
ability of the particle-based methods in modeling highly nonlinear
hydrodynamics, some shortcomings, such as unstable pressure computation and
high computational cost remains. In order to assess the performance of these
two methods, the weaklycompressible SPH (WCSPH) parallel solver, DualSPHysics,
and an in-house incompressible MPS solver are adopted in this work. Two test
cases consisting of threedimensional (3D) dam-break problems are simulated, and
wave heights, pressures and forces are compared with available experimental
data. The influence of the artificial viscosity on the accuracy of WCSPH is
investigated. Computational times of both solvers are also compared. Finally,
the relative benefits of the methods for solving free-surface problems are
discussed, therefore providing directions of their applicability.
