Tribology of tidal turbine blades: impact angle effects on erosion of polymeric coatings in sea water conditions

Tidal energy, of all marine renewables energies, possesses higher persistency and predictability over long time scales. Due to the aggressive marine environment, there are barriers in the development of tidal power generation technology. In particular, with regard to increased rotor diameter, the selection of material presents significant challenges to be addressed including the tribological environment, such as solid particle erosion, cavitation erosion, the effect of high thrust loading on the turbine blade tips, and the synergy between sea water conditions and such tribological phenomena. This research focuses on producing and testing a variety of advanced materials and surface coatings to investigate two main tribological issues in tidal environments: matrix cutting and reinforcement fracture. In our previous work, a G10 epoxy glass laminate was tested in this environment and the results revealed tribological issues. In this present work, G10 epoxy glass laminate base erosion resistant polymeric coatings have been tested for the range of sand particles size in our our previous work and in NaCl solution. The test results reveal that the coating has enhanced the quality of performance of the composite with respect to tribological behaviour, and has diminished the synergy between sea water and tribological phenomena. This indicates progress toward the selection of advanced materials to manufacture tidal turbine blades.