Abstract
The generation of electricity from free-flowing water is an important renewable energy source. In this paper, we introduce a new turbine concept based on a vertical axis turbine with two extraction planes and a rectangular harvest area suitable for rivers or ocean currents. Using numerical simulations, we show that the extension of the classic vertical axis turbine by linear sections can significantly improve efficiency, with gains of up to 12% in the case of the Reference Model 2 turbine, a benchmark prototype used for comparison. Based on the findings, a prototype is designed and built with a focus on optimizing the blade pitch using computational fluid dynamics simulations. The prototype is subsequently evaluated through performance measurements on a test boat. Our results show that the Linear Turbine has the potential to significantly improve the efficiency of kinetic energy converters for free-flowing water, with an efficiency of around 42% achieved in our small prototype. Key features of the turbine include its ability to generate electricity from rivers and ocean currents with minimal impact on the natural environment, its high potential efficiency, vertical construction, and linear working range. The design of the turbine is complex, but its potential applications include use in small-scale systems and as a environmental alternative to traditional hydroelectric dams. Further investigations are needed to focus on economic design and to validate improved designs with 3D fluid simulations.