Rain erosion maps for wind turbines based on geographical locations: A case study in Ireland and Britain
Springer|K. Pugh and M. M. Stack|Jan 1, 2021
This paper examines the rate at which turbine blades erode from exposure to rainfall. The authors attempt to assess those areas within the UK and Ireland where blade degradation is likely to occur at faster rates. The abstract and conclusion sections of the paper are provided below. The full report can be downloaded from the document links on this page.
This paper examines the rate at which turbine blades erode from exposure to rainfall. The authors attempt to assess those areas within the UK and Ireland where blade degradation is likely to occur at faster rates. The abstract and conclusion sections of the paper are provided below. The full report can be downloaded from the document links on this page.
Abstract
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.
Conclusions
In conclusion, the data from the rainfall within the UK and Republic of Ireland were formatted together to produce an Ireland/Britain map showing the average rainfall across the two countries in both January and May averaged over the last 20 years. These maps were then used as the basis for an erosion experiment converting the rainfall to exposure time within the erosion rig. These results were then arranged on the map to display the degradation of the turbine blades from rain droplet impacts. This was coupled by a saltwater erosion experiment that used 3.5% saline solution as the droplets to simulate offshore wind turbines which are subject to being eroded by sea water (salt spray corrosion enhanced erosion) in the atmosphere. These two maps were then superimposed to display areas of frequent hail and the locations of each country’s largest wind turbine farm. This was carried out
in an attempt to visualise the erosion patterns across both Ireland and the UK.
It is clear that the general trend consists of greater erosion in the west coast of both the UK and The Republic of Ireland with the highest erosion areas being the north west of Scotland where the land tends to be at a higher elevation and also the south west of Ireland where there is no protection from the prevailing wind over the Atlantic. The locations of frequent hailstorms across the UK and the republic of Ireland could be considered stochastic, however, the locations of some major wind farms overlap with frequent hail; this can be seen predominantly in Northern Ireland. This overlap could potentially reduce the lifetime of the turbine blades at an increased rate due to more powerful impacts from hailstones.
These mapping methods have potential to be used in lifetime modelling of wind turbine blades and have the possibility to be developed into a dynamic map that can display changes in new wind farms and changing climates. This is particularly important due to weather changes over long periods of time on the annual cycle.
