Validation of the low dissipation computational algorithm CABARET-MFSH for multilayer hydrostatic flows with a free surface on the lock-release experiments

Abstract

The article presents the results of validation in lock-release experiments of a new low-dissipative multilayer hydrostatic model CABARET-MFSH. This model describes the dynamics of fluid with variable density and free surface. The computational algorithm of the new model is based on the method of hyperbolic decomposition, which presents of a multilayer structure in the form of separate layers interacting throughout interfaces. An explicit CABARET scheme is used to solve the system of hyperbolic equations in each layer. The scheme has a second order of approximation and is time reversible. Consequently, the scheme is initially non-dissipative. Besides, mass and momentum exchange between layers and filtering of flux variables are used to regularize the multilayer hydrostatic model, which introduces additional numerical dissipation into the scheme. The parameters of the filtering procedure are determined empirically from the condition of the stability of the algorithm and the minimal of the scheme viscosity. A 2D spatial version of our model is used for modeling lock-release experiments described in this article due to the uniformity of the current in the transverse direction. The results of numerical calculations are in satisfactory agreement with experimental data.