Impact of macro-turbulent structures from mooring anchors and rough riverbeds on the performance of a horizontal axis hydrokinetic turbine
| dc.contributor.author | Ekezie, Sixtus | |
| dc.contributor.examiningcommittee | Derksen, Robert (Mechanical Engineering) Miroslava, Kavgic (Civil Engineering) | en_US |
| dc.contributor.supervisor | Bibeau, Eric (Mechanical Engineering) | en_US |
| dc.date.accessioned | 2018-11-06T21:04:41Z | |
| dc.date.available | 2018-11-06T21:04:41Z | |
| dc.date.issued | 2018 | en_US |
| dc.date.submitted | 2018-11-04T23:05:53Z | en |
| dc.degree.discipline | Mechanical Engineering | en_US |
| dc.degree.level | Master of Science (M.Sc.) | en_US |
| dc.description.abstract | Reported are laboratory and field measurements obtained to characterize the flow structures caused by mooring anchors and rough river beds on the performance of hydrokinetic turbines. Series of flow velocity profile in-situ measurements characterize the energetic flow at the Canadian Hydrokinetic Turbine Test Centre (CHTTC) located on the Winnipeg River. Using an acoustic Doppler velocimeter, a novel method was applied to obtain the flow velocity through the water column to contribute to the design and optimization of power production from a hydrokinetic turbine. The acoustic Doppler velocimeter measures the mean and fluctuating velocity components at a frequency of 64 Hz. Tests were performed between 2.1 and 2.7 m/s upstream and downstream of turbine mooring anchors. Anchors occupy 12% of the water column height. Near-surface measurements show a 9.9% increase in turbulence intensity and 8.8% increase in free-stream velocity due to the upstream turbine mooring structures while the profile measurements show a temporal variation in the velocity and turbulence intensity profiles. In a more detailed laboratory investigation, four different scaled geometries of turbine mooring anchors were designed, fabricated and tested, including a 19.8 cm diameter horizontal axis turbine in a water tunnel. Tests are first performed at a steady velocity of 1.1 m/s and at an unobstructed Reynolds number of 217000 based on rotor diameter. During this testing, velocity measurements were taken at different locations upstream of a scaled horizontal turbine to determine the optimum operating conditions in a steady free-stream velocity. Furthermore, 25 surface roughness and four mooring anchor geometries were tested and located 2 and 3 rotor diameter upstream of the turbine in the water tunnel. Results show a 14% to 36% increase in turbine performance due to the impact of mooring anchor geometries and surface roughness. These results are useful in choosing a turbine mooring anchor design, geometry, and location to enhance turbine performance and obtain an understanding of a rough riverbed at the energetic river site. | en_US |
| dc.description.note | February 2019 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/33554 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Macro-turbulent structures, Turbine mooring anchors, Water tunnel | en_US |
| dc.title | Impact of macro-turbulent structures from mooring anchors and rough riverbeds on the performance of a horizontal axis hydrokinetic turbine | en_US |
| dc.type | master thesis | en_US |