Optimized blade design of a radial implulse turbine for wave energy conversion

Nowadays, wave energy exploitation is of great interests due to its sustainability, reliability and large potential. This paper aims to improve the rotor blade performances especially the efficiency of a self-rectifying impulse radial turbine which is in use in OWC devices. Symmetrical blade profile based on use of circular arcs and straight lines has been adopted. A new procedure for optimizing the geometrical blade parameters has been implemented in this work. The Design of Experiments (DOE) method has been adopted with 4 blade geometrical parameters and 2 levels for optimizing the number of numerical tests to determine the optimal profile equilibrating the efficiency between exhalation and inhalation modes. Numerical simulations in the whole turbine geometry have been carried out with ANSYS FLUENT for efficiency computation. Significant differences in this parameter have been noticed by varying the rotor blade profile. Optimal rotor geometry in both modes is obtained with a maximum efficiency of about 70 %.