A numerical investigation into the effect of diffusers on the performance of hydro kinetic turbines using a validated momentum source turbine model

• Published in: Renewable energy Vol. 35; no. 6; pp. 1152 - 1158
• Main Authors: Gaden, David L.F., Bibeau, Eric L.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.2010; Elsevier
• Subjects: Applied sciences; Channels; Density; Diffuser; Diffusers; Energy; Energy of waters: ocean thermal energy, wave and tidal energy, etc; Exact sciences and technology; Hydraulic turbines; Kinetic hydropower; Marine current turbine; Mathematical models; Momentum source model; Natural energy; Oceans; River kinetic turbine; Strategy; Turbines; Canada, Ontario, Current R; Diffuser; Momentum source model; Kinetic hydropower; Marine current turbine; River kinetic turbine; Ocean energy; Process improvement; Performance characteristic; Turbine; Modeling; Optimization; Numerical simulation; Electric power production; Performance
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2009.11.023

Kinetic hydropower involves the use of hydro turbines, submerged within existing currents for power generation. They are applicable to ocean and tidal currents, rivers, and human-made channels. This versatility gives them advantages over conventional hydropower, however they suffer from low power densities. This numerical study investigates the use of diffusers to enhance the performance and viability of kinetic hydro turbines. To simplify the problem, the turbine is modeled as a momentum source region, a strategy that is first validated against Betz theory. The diffuser configuration produces 3.1 times more power than the turbine with no diffuser. A scaling analysis also shows a turbine with a diffuser outperforms a larger size turbine with no diffuser.