Abstract: This work deals with the conception, from a mechanical and electrical point of view, of an impulse axial turbine for an oscillating water column (OWC) plant. Air turbines for wave energy conversion have a special feature to be taken into account: these turbines are self-rectifying and work with a cyclically bidirectional air flow alternatively as an inflow/outflow turbine.
The turbine geometry proposed in the bibliography has been used. A previously developed numerical CFD (Computer Fluids Dynamics) model has been used to improve aerodynamically the internal geometry of the turbine. With a better efficiency, the impulse turbine is now attractive for the industry. In order to start the industrial design, some specifications expected for the turbines have been underlined. The nominal power will be 20kW.
To carry out a global mechanical design of the turbine, the first step was principally to propose a feasible structure, easy to assemble and guarantee easy maintenance. The interaction between the turbine and the generator is an important factor, which has a direct influence on the global efficiency of the OWC plant.
Therefore, it has been necessary to study both the dynamic and electrical behaviour in order to control the turbine operations. Specifically, the evolution of the power provided by the swell over the time is taken into account.
