Abstract
Tidal stream energy is a low-carbon energy source. Tidal stream turbines operate in a turbulent environment, and the effect of the structure between the turbine and seabed on this environment is not fully understood. An experimental study using 1:72 scale models based on a commercial turbine design was carried out to study the support structure influence on turbulent intensity around the turbine blades. The study was conducted using the wave-current tank at the Laboratory of Maritime Engineering (LABIMA), University of Florence. A realistic flow environment (ambient turbulent intensity = 11%) was established. Turbulent intensity was measured upstream and downstream of a turbine mounted on two different support structures (one resembling a commercial design, the other the same with an additional vertical element), in order to quantify any variation in turbulence and performance between the support structures. Turbine drive power was used to calculate power generation. Acoustic Doppler velocimetry (ADV) was used to record and calculate upstream and downstream turbulent intensity. In otherwise identical conditions, performance variation of only 4% was observed between two support structures. Turbulent intensity at 1, 3 and 5 blade diameters, both upstream and downstream, showed variation up to 21% between the two cases. The additional turbulent structures generated by the additional element of the second support structure appears to cause this effect, and the upstream propagation of turbulent intensity is believed to be permitted by surface waves. This result is significant for the prediction of turbine array performance.
Highlights
The existence of climate change is unequivocal
Experiments conducted on 1:72 scale models of a tidal turbine with two different support structure designs suggest that the variation in support structure design has an impact on the turbulent intensity upstream and downstream of the support structure, and over the water depth at the blade swept region
The turbulent region generated around a tidal turbine is of critical importance to a device developer seeking to achieve maximum performance at both device and array scale
Summary
The existence of climate change is unequivocal. Scientific data illustrates that the burning of fossil fuels has a role in the world’s climate. Since the industrial revolution [1], the use of fossil energies has increased the level of atmospheric greenhouse gases including CO2 , which reflect heat back towards the earth rather than allowing it to escape, leading to an increase in global temperatures. Following the production of a framework at the 2015 global climate change summit in. Electricity generation is the single largest source of greenhouse gas emissions both as a global average and in most countries. The move towards a future based on the generation of energy from lower carbon sources, avoiding the high CO2 emissions associated with electricity generation from fossil fuels, is an important part of efforts to reduce greenhouse gas emissions and slow global temperature increase
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
