Nesterov O. A numerical non-hydrostatic model for hydrodynamic simulations in stratified water bodies of complex shape

A complex model for the numerical simulation of hydrodynamic and thermodynamic fields in water bodies with free surface has been developed. The model takes into consideration the basic factors and processes, which are specific for coastal waters of seas, lakes and rivers. A method for the numerical integration of RANS equations in single and double-sigma coordinate systems, which allows for carrying out simulations either taking into account the full pressure or using the hydrostatic pressure approximation, has been elaborated. In a result of the application of this model, it was found that the bed roughness has a significant impact on the transformation of waves over a submerged obstacle; it was shown that the settling of solid particles in gravity flows affects overall characteristics of such flows; it was revealed that the presence of a narrow but relatively deep navigational channel in the Dnepr-Boog estuary plays an important role in its ecosystem.