Abstract
Free surface flow problems occur in disaster simulations such as tsunami flow in urban area. In this situation, a non-hydrostatic free surface model is required to perform a tsunami inundation simulation. It is, however, difficult to carry out three-dimensional large-scale tsunami simulations because of the computing of the pressure Poisson equation in the incompressible flows.
In current study, we have developed a fully explicit three-dimensional free surface model by the lattice Boltzmann method with the Piecewise Linear Interface Reconstruction approach. In addition, we have used pseudo Level Set function generated by the interface fraction to determine the interface normal vector accurately based on the Simple - Coupled Level Set and Volume of Fluid method. Through the classical dam-breaking problem, we demonstrated that our model has a convergence of model accuracy according to the spacing grid sizes. Besides, our model can calculate the interface shapes seamlessly and settle the artificial oscillations.