Mathematische Modelle zur Simulation von Zirkulationsströmungen in einem See

The three-dimensional, finite-difference model of R.L. Street (Stanford University) has been adapted at the simulation of wind-induced currents in the northern basin of the Lake of Lugano. The model makes use of complete Navier-Stokes equations and a dynamical algorithm to calculate the eddy viscosity. The model predictions are compared with data collected in the measure campaign of 1979. A further application of the model is the cold inflow simulation in a stratified basin with inclusion of turbulent vertical exchange processes. A two-dimensional version of the model, which assumes an hydrostatic pressure distribution, is utilized to simulate the thermal sommer development of the Lake of Lugano, during 40 days. The model includes the thermical interactions and the wind influence. The results obtained show the possible application of the three-dimensional model to the currents simulation in lake basins. The two-dimensional model may be utilized to predict the development of a basin subject to a thermal load.