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.

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.

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Within renewable energy, challenging climates can impose great limitations on power generation. In wind energy, rain erosion on turbine blades can create major disruptions to air flow over the aerofoil, reducing the efficiency of the blade and immediately affecting the power output of the turbine. The defects in the materials that cause these inefficiencies are known and can be observed on turbines that have been in operation for extended periods. This work explores the transitions between different wear states for G10 Epoxy Glass under laboratory simulated wind turbine conditions in operation and measures the wear periodically to identify a progression of erosion. Mass loss data and micrographic analysis revealed samples at 45° and 60° displayed increasing erosion when examining erosion performance for angles between 15° and 90° over various exposure and velocities. Erosion maps were constructed, showing the variation of wastage and identifying the performance window of conditions where degradation is minimised.

Erosion rates of wind turbine blades are not constant, and they depend on many external factors including meteorological differences relating to global weather patterns. In order to track the degradation of the turbine blades, it is important to analyse the distribution and change in weather conditions across the country. This case study addresses rainfall in Western Europe using the UK and Ireland data to create a relationship between the erosion rate of wind turbine blades and rainfall for both countries. In order to match the appropriate erosion data to the meteorological data, 2 months of the annual rainfall were chosen, and the differences were analysed. The month of highest rain, January and month of least rain, May were selected for the study. The two variables were then combined with other data including hailstorm events and locations of wind turbine farms to create a general overview of erosion with relation to wind turbine blades.