Advances in the design of a multi-stage hydrokinetic turbine
Germán Alejandro Ibarra Bolaños1; Geraldo Lúcio Tiago Filho1; Ramiro Gustavo Ramírez Camacho1
1 Universidade Federal de Itajubá
doi:10.20906/CPS/COB-2015-0574
Resumo
The energy of waterways is harnessed by hydrokinetic devices, namely, turbine and oscillating systems. Current trends are focused on the use of farms and multi-rotor units in order to increase both, efficiency and energy generation. The use of farms deals with research about arrays of modern-design systems and the interference between each other. For other hand, multi-rotor systems involve research and development of new technologies. This is the case of the multi-stage hydrokinetic turbine, a system in which several rotors are mounted on the same rotating shaft. Here, we present the results obtained so far about the performance in free and confined flows. These data was obtained from computational modeling and experimental tests, involving two rotor geometries. Indeed, efficiency increases to 78%, exceeding the Betz limit, for three rotors under the effects of blockage area ratio. Research continues to determine the best operating conditions of the system.
Palavras-chave: Hydrokinetic energy; Multi-stage turbine; Efficiency gain; Computational fluid dynamics