Calculation of Lake-Circulation with Threedimensional Finite Elements

Abstract

Limnologists, studying biological and chemical processes in lakes know about the importance of physical transport processes, induced by wind, temperature differences, in- and outflows. For these purposes, a lot of models are developed which calculate the currents and the temperature in lakes. Normally, twodimensional vertically-integrated models are used, with the assumption of hydrostatic pressure distribution. In certain cases, when vertical acceleration cannot be neglected, threedimensional models should be used. An example is the artificial aeration of lakes by blowing air in the anaerobic layers near the bottom, which causes strong upward velocities.