This paper represents the investigation of rain erosion on wind turbine blade materials under load in the simulation of onshore and offshore environmental conditions. The experimental work was carried out on a whirling arm rig with the material under a static 3 point bend to simulate large multi-megawatt wind turbine blades flexing during operation. This experiment was run with both fresh water and salt water to simulate onshore and offshore turbines. The results showed that the effects of a pre-stress on the samples resulted in a higher degradation rate following rain drop erosion. The microscopic analysis of the samples exposed to pre-stress identified distinctive surface features which has been termed a surface impact circular deformation. These features showed signs of cracking which enhanced the erosion rate. The pre-stressed samples also encountered a larger crossover in erosive mechanisms of abrasion and direct impacts; this was theorised to be due to the material being close to its yield stress and more likely to plastically deform.

This paper represents the investigation of liquid impacts on wind turbine blade materials in the simulation of onshore and offshore environmental conditions. G 10 epoxy glass laminate was used as a specimen material. The experimental work was carried out on a raindrop erosion test rig at the varying angles of attack for a range tip speed. Two solutions, i.e. pure and salt water, were used to highlight the effects of offshore environment on this material when it is being used as wind turbine blades. Test results show that the erosive wear increased with an increase in droplet impact velocity. Erosion mapping techniques were used to compare the erosive wear behaviour of this material for application to onshore and offshore applications as candidate wind turbine materials.

Wear and corrosion in artificial hip replacements are known to result in metal ion release and wear debris induced osteolysis. This may lead to pain and sensitivity for patients. This infers that pre-clinical testing is critical in determining the long-term performance, safety, and reliability of the implant materials. For this purpose, micro-abrasion-corrosion tests were carried out on a biocompatible material, Ti-6Al-4V ELI, using a T-66, Plint micro-abrasion test rig in conjunction with Gill Ac corrosion testing apparatus for the range of applied loads and electrical potentials in the hip joint simulated environment. A Ringer’s solution, with and without an abrasive particle (silicon carbide), was used to enable the interactions between abrasion and corrosion. In this paper, the effects of applied load and electrochemical potential on the tribo-corrosion behaviour of Ti-6Al-4V in a bio-simulated environment are presented. The wastage, micro-abrasion-corrosion mechanisms, and synergy behaviour were identified and mapped. A significant difference in corrosion current densities was observed in the presence of abrasive particles, suggesting the removal of the protective oxide layer. The results also indicate that Ti-6Al-4V had significant abrasive wear loss when coupled with a ceramic counterpart. According to the mechanism, micro-abrasion plays a predominant role in the abrasion-corrosion behaviour of this material and the material losses by mechanical processes are substantially larger than losses, due to electrochemical processes.

Climate change is rapidly forcing the world to create renewable energy that is capable of sustaining future energy requirements globally. The generation of renewable energy at a comparatively lower cost is a major challenge for this industry. Unforeseen weather conditions and environments such as offshore conditions or involving acid rain have a significant effect on the degradation of structural materials of renewable energy devices. For the investigation of droplet erosion behavior of the advanced material for the wind turbine blades, experimental work was carried out on a glass fiber-reinforced epoxy (GFRE) composite in different environments. A whirling arm rig was used for this experimental work in a laboratory-simulated rainfall conditions at a constant tip speed of the rotor blade. Three types of rainwater were used for a range of angles of attack from 15 to 90 deg in an increment of 15 deg. Erosive wear maps have been constructed to show the weather, location, environment, and raindrop erosion effects on the degradation of the wind turbine blade material. This map predicts that erosion in saline and acidic rain conditions acts synergistically on the blade material, which results in delamination between the fiber layers, pit formation, and development of micro stresses leading to loss of adhesion of reinforcement fibers.

This paper presents a study of the erosion resistance of coated and uncoated polymer matrix composites for tidal turbine conditions. It focuses on the development of comparative erosive wear mode and mechanism maps for such materials. In our earlier work, i.e. testing of glass fibre reinforced polymer composites for tribological applications in marine simulated conditions, several erosion related issues were highlighted. The combined effects of the NaCl solution and sand enhanced the erosive wear dramatically of the uncoated specimens. In order to address those issues, an erosion resistant polymeric coating was applied to the composite and tested in marine simulated conditions with an extended range of sand particle size. The test results of the uncoated and coated composite have been compared in this research by erosive wear mode and mechanism maps techniques. These maps reveal that the coating has enhanced the erosion resistance. These findings provide significant progress towards materials selection approaches to manufacture of tidal turbine blades.

Tidal energy, of all marine renewables energy, possesses higher persistency and predictability over long-time scales. Moreover, the higher density of water than air also results in greater power output from a tidal turbine than a wind turbine with similar dimensions. 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 composite materials with different fibres and reinforcement layouts to evaluate two main tribological issues in tidal environments: matrix cutting and reinforcement fracture. A slurry pot test rig was used to measure the effects of different impact angles and particles sizes at constant tip speeds.