Smart blade tip design prevents vortex
Brand new start-up nigeQ is ready to test an innovative blade tip that eliminates vortex at the end of turbine blades. The Infinite Wing is expected to increase overall electricity production up to 10% or more. In addition, it reduces noise and mast vibrations. The entire wind farm even benefits from less wear and tear on rotating parts. The search for a test location has top priority, says CEO Eelco de Boer.
For which problem did you find a solution?
“Onshore and offshore wind turbines suffer from inhibiting vortex. Due to this turbulence, the blades rotate less easily, impeding the performance of the turbine. Vortex is a well-known phenomenon with aircraft wings and wind turbine blades that both work with underpressure and overpressure. Vortex, which can last for minutes, causes noise and vibrations in the mast: every time a blade passes the mast, the air stream ‘hits’ the mast. The vibrations propagate through water or soil. The turbulence also affects the other turbines in the park. As a result, components such as bearings, drive shafts and gearboxes are subject to wear. Existing solutions such as tabs? or generators on the blade tips lead away the vortex or cause smaller vortex to reduce the larger ones. They do not resolve vortex. Our Infinite Wing does that. "
What is the core of your solution?
“Vortex is created by the pressure drop of the air towards the end of the turbine blade. The Infinite Wing is designed to manipulate the air flow in such a way that no vortex occurs. The top and bottom of the blade tip have slots through which the air flows. The air flow is ingeniously changed direction, preventing vortex. How exactly is the secret of the blacksmith?
The Infinite Wing is a 1997 invention of two brilliant British aviation engineers, John J.A. Smith and Roger E Read. They worked on this at intervals and applied for a patent in 2007. Although the aircraft industry is very interested, it has not been applied yet. The blade tip for aviation is ready for the market. Five years ago, the two inventors started designing a wind turbine blade. We took over this work from them. We established nigeQ in early 2020, named after an easterly wind on Greenland.”
What is so pioneering about the Infinite Wing?
“This is the first time that vortex at the end of the wind turbine blade will be resolved. Not led away or reduced, but really prevented. This is how you tackle the problem at the source. Our solution is a fundamentally different way of approaching the problem."
What are the benefits of your solution?
"A substantial increase in electricity production. Flow model calculations show an additional performance of 10%, but it could also be 20% according to a CID analysis (?). This is unprecedented for a discipline that is normally happy with tenths of percent. You can also say that with the same turbine you can equal the yield of a larger turbine. This is relevant, for example, for installers who are reaching the limits of what their current installation vessels can handle.
In addition, the blade sweeps quieter and softer along the mast. This reduces the low-frequency noise. Due to the noise nuisance, Germany has increased the minimal distance between wind farm and habitation from 400 to 1000 meters. At sea it is perhaps more relevant that the mast has fewer vibrations. The fewer vibrations, the fewer vibrations propagate through the water. That benefits marine life.
Furthermore, the other turbines will have less trouble with turbulence. The nearby turbines wear faster due to these forces. Sometimes bearings, drive shafts or gearboxes must be replaced after a few years. According to calculations, the service life of bearings could increase from three to five years with our tips. At the same time, it means that we could extend the economic life of a wind farm."
How far are you now?
“The design is ready. We are about to apply for a worldwide patent. We are now in the ‘Proof of Concept’-phase: prove in practice that the model calculations are correct. We are looking for a suitable location to test the Infinite Wing in the field. We want to test our blade tip in an existing wind farm to measure exactly what the influence of our blade tip on efficiency, noise and nearby wind turbines is under different weather conditions, wind speeds and temperatures.
We are also looking for partners. We are talking to LM, a major Danish manufacturer of wind turbine blades. Vestas shows interest as well. Van Oord is interested because it allows them to install wind turbines with a higher energy yield with their existing installation vessels. Co-operation with the Eneco’s or Vattenfalls of this world is also an option."
What are your challenges?
“Finding a location where we can test the blade tip for a period of 3-4 months is the most important right now. We want to co-operate, but not too exclusively with a single company that wants to keep the results to itself. That is a dilemma."
What are your next steps?
“Expand our network. The ultimate goal is to license the Infinite Wing to the market and to offer corresponding services. We are not going to produce the blade tip ourselves. Therefore, we are also looking for license partners. If we have tested the blade tip, we want to optimize the design. We want to engage aerodynamic engineers for this purpose. We are already in contact with Swansea University, but we also want to connect with TU Delft and the University of Twente.”
What are the benefits of Offshore Wind Innovators and TKI Wind op Zee?
“We prefer to test in an independent setting. Hopefully, TKI Wind op Zee can help to realise that. They have a large network. An event like the Matchmaking Day offers a good platform to pitch our innovation. After the field test, we want to delve into the funding and research options.”