Computational fluid-dynamic analysis of an automated floodgate for capacity gains in hydroelectric powerplants

Análise de dinâmica dos fluidos computacional de uma comporta automatizada para aumento de capacidade em usinas hidrelétricas

Brazil has an elevated dependence on hydroelectric powerplants, both in terms of production of renewable energy as well as providing stability to the energy grid while using intermittent energy sources. Despite these challenges, the country currently encounters environmental and social restrictions to build new dams. Thus, the use of alternatives to improve efficiency, such as heightening reservoir walls through the use of floodgates, has become more relevant. The dimensions of these systems should be determined in order not to compromise the reservoir’s safety. In light of this, this study presents the hydrodynamic evaluation of a heightening system for capacity gains, flow control, and increasing energy generation at the Cipó hydroelectric plant in southern region of the state Minas Gerais, Brazil. The heightening system proposed in this study is based on an automated floodgate with a curvilinear profile. The analyses were conducted in a physics laboratory as well as virtually through computational fluid dynamics (CFD) tools. To model the problem, a two-phase steady state flow was adopted. The floodgate demonstrated satisfactory behavior, capable of opening and closing as the static pressure from the water volume overloaded its center of gravity, controlling the volume within the reservoir.

Keywords:
Automated floodgate; Reservoir; Dam, spillway; Computational fluid dynamics; Free surface