About Task 46

Leading-edge erosion (LEE) has been identified as the main factor substantially reducing both blade lifetime and energy output over time. Field repairs are costly due to lost availability and challenging access and weather conditions. It is crucial to understand the impact of leading-edge erosion on the performance of wind plants to be able to determine the cost/benefit of proposed mitigation strategies.

In this context, Task 46 has been formed by experts from different disciplines to work together to achieve a better understanding of the key technical challenges in blade erosion. The Task will produce literature surveys, topical reports, recommended practices, and models.

The Task 46 scope is aligned to two research priorities established by IEA TCP Wind: site characterization and advanced technology.

What are IEA Wind Tasks?

The IEA Wind Technology Collaboration Programme’s (TCP) cooperative efforts continue to advance the technological development and global deployment of wind energy technology. The IEA Wind TCP is a vehicle for member countries to exchange information on the planning and execution of national large-scale wind system projects, and to undertake co-operative research and development (R&D) projects called Tasks.


Participation in a research Task is open to any organization located in Member Countries or Sponsor Members of the IEA Wind TCP. Cooperative research is carried out as research, development, and deployment projects of the IEA Wind TCP. Technical reports, fact sheets, and recommended practices are released publicly to benefit the wind energy community.


Check out the full list of IEA Wind Tasks.


Work Plan

The Task work plan is structured in four technical work packages (WP2-WP5) supported by a management work package (WP1), delivered during a period of four years March/2021 – February/2025.

Each work package is split into activities, with at least one deliverable per activity. The deliverables are IEA Wind reports, Recommended Practices, Metadata with links to critical datasets, plus new models. It is anticipated that the work performed in the task will complement other research efforts by participants, in the context of international or national R&D projects.

The scope of each work package is listed below:

Work Package 1


WP1.1 Develop and maintain Task data workspace and website participants

WP1.2 Technical support to task participants to ensure review & quality of deliverables

WP1.3 External communications

WP1.4 Preparation & chair of coordination meetings for all Task participants

WP1.5 Preparation & chair of webinars for dissemination

WP1.6 Reporting to IEA Wind ExCo

Work Package 2

Climatic Conditions

WP2.1 Definition of priority geographic areas for geospatial mapping of erosion potential.

Compile comprehensive meta-data regarding available hydrometeor data (e.g. rain, hail characteristics, and co-availability of wind speeds) for assessing LEE with a particular focus on regions with major wind energy penetration. The deliverables will be a report & spreadsheet summarizing the meta-data. In the report, we will document where there are sufficient & sufficient quality data available for parameters of crucial importance to characterizing LEE.


WP2.2 Identification of additional meteorological parameters for erosion.

Compile comprehensive meta-data regarding available data for additional parameters of importance to LEE–specific foci; wind-blown dust, UV, the occurrence of freezing rain, and corrosive agents such as sea spray. The deliverables will be a report & spreadsheet summarizing the meta-data. In the report, we will document where there are sufficient & sufficient quality data available for parameters of crucial importance to characterizing LEE.

Conduct comprehensive literature reviews and synthesize knowledge gained from projects in order to better characterize:


WP2.3 hail, rain & dust climates in target areas


WP2.4 hydrometeor droplet size distribution as a function of climate


WP2.5 Revisit data availability and quality for key meteorological parameters of relevance to LEE.



WP2.6 Develop a roadmap for a leading-edge erosion atlas

Including developing Recommended Practice (RP) for use of meteorological data for determining Leading Edge Erosion (LEE) classes.


WP2.7 Develop Recommended Practice (RP) for measurements of LEE drivers

Including metrology development and prospects for establishing ‘super sites’ for instrument testing and model V&V exercises.


WP2.8 Advance methods to conduct model V&V

Exercises focused on LEE and improve modeling tools of key atmospheric properties.

Work Package 3

Wind Turbine Operations with Erosion

WP3.1 Model to predict annual energy production loss based on blade erosion class.

Develop a common model of aerodynamic performance loss due to leading-edge roughness and erosion standardized classes. Quantification of performance degradation (loss of AEP) as a function of roughness and ‘erosion climate’.


WP3.2 Report on standardization of damage reports based on erosion observations.

Standardization of damage reports for validation of any erosion potential assessment and to allow effective integration of data from operators with laboratory-derived estimates.


WP3.3 Droplet impingement model for use in fatigue analysis.

Step 1: Characterization of aerodynamics for droplet impingement probability.

Activity: Develop a standard model for droplet impingement, validated with wind tunnel experimental data.


WP3.4 Potential for erosion safe-mode operation.

A report describing the potential for leading-edge erosion safe mode operation. This report will be used for seeking participation from industry and research funders towards a coordinated project designed to assess the viability and cost-benefit of leading-edge erosion safe mode operation.


WP3.5 Accuracy of LEE performance loss model based on field observations (validation).

Validation of performance loss model using wind tunnel and field observations. Carry out iterative aerodynamic loss benchmarks with model development and new wind tunnel testing for calibration and validation. Validation of complete performance loss model using probabilistic analysis of field observations. Adapt models to simulate high roughness values (up to P20).

Work Package 4

Laboratory Testing of Erosion

Copyright Video by Nicolai Frost-Jensen Johansen


WP4.1 Available technologies for lab tests (report).

Production of a report on technologies available for the laboratory evaluation of erosion. The review aims at covering as much as possible of laboratory testing relevant for wt blade erosion, ranging from formulation and micro-structure over basic physical, chemical, and mechanical properties to rain erosion resistance. Topics include:
– Rain erosion tests
– Impact tests
– Viscoelastic properties
– Fracture mechanics
– Fatigue
– Microstructure Characterization
– Aging, etc.


WP4.2 Erosion failure modes in LE systems (literature review).

Literature review and partner experience document on failure modes associated with the erosion process. The task is divided into WP4.2a “Failure modes in laboratory testing”, running in parallel with WP4.1 and WP 4.2b “Failure modes on turbines in the field”. The work will be performed in alignment with WP3.2 and WP5.2.


WP4.3 Normalization of test substrates (recommended practice).

Development of a recommended practice on the normalization of test substrates for rain erosion testing.


WP4.4 Pre-evaluation of test specimens (recommended practice).

Development of a recommended practice on the pre-evaluation of test specimens.


WP4.5 Test data analysis, damage accumulation, and VN curves (recommended practice).

The scope is damage accumulation based on slice length, the time between intervals and tip speed, data analysis, and generation of VN curves. Work will be performed in alignment with WP5.3.


WP4.6 Simple mechanical test for screening of key parameters (report).

Laboratory simple mechanical testing and identification of indicative key parameters for pre-evaluation of erosion resistance. Work will be performed in alignment with WP5.3.


WP4.7 Correlation between RET data and expected field service life (report and model).

Correlation model to read across laboratory erosion metrics to field erosion metrics. Work will be performed in alignment with WP2.7.


WP4.8 Aging – unloaded and during testing (literature review and recommended practice). Aging. Environmental and chemical aspects of degradation in an unloaded condition (Aging ex-situ) and during testing (stress cycle induced chemical degradation).

Work Package 5

Erosion Mechanics and Material Properties

WP5.1 Damage models based on fundamental material properties.

Identify appropriate damage models for accumulative droplet impact erosion attending specific failure modes based on fundamental material properties. Define appropriate testing methodologies for the material properties defined as input parameters in the modeling. Work will be performed in alignment with WP2.8 and 3.3 (modeling including droplet impingement aerodynamics and key atmospheric issues) and WP4.7 (modeling from RET Data).

Report 1 based on Literature Review: Identify the lacks and drawbacks of state-of-the-art erosion damage modeling techniques and corresponding material characterization including partner’s experiences.

Report 2 is based on alternative/complementary erosion damage model studies including partner’s experiences.


WP5.2 Multilayer systems.

Consider the leading edge as a multilayer system, and the different modeling approaches (in relation to 5.1). Appropriate analysis for Manufacturing issues due to LEP configuration, application procedure, and LEP blade integration technology.

Report 1 based on Literature Review: LEP multilayer technology and interface modeling methodologies.

Report 2 is based on alternative/complementary interface damage mechanisms studies and related modeling techniques including partner’s experiences.


WP5.3 Microstructure and macroscopic material properties.

Connecting the observed macroscopic mechanical behavior with the polymer composition and microstructure. Investigating the effect of fillers, additives, and polymer composition, on erosion mechanics and accumulation damage. To investigate testing techniques for polymer system analysis linked with the erosion damage progression.

Report on the material microstructure and macroscopic material fundamental properties in relation to erosion performance.

Task 46 Roadmap


Kick-off meeting

First Deliverable D2.1


First outreach webinar (Q2)

Deliverables D2.2, D2.3, D2.4, D4.2, D5.1.1, D5.2.1


Outreach webinar (Q2)

Deliverables D2.5, D2.6, D3.3, D4.3, D4.4


Outreach webinar (Q2)

Deliverables D2.7, D4.6, D5.1.1, D5.1.2


Final outreach webinar & dissemination event (Q1)

Deliverables D2.8, D3.5, D4.7, D4.8 D5.3

Operating Agent Charlotte Bay Hasager

Professor, Department of Wind and Energy Systems

DTU Wind and Energy Systems

DTU Wind and Energy Systems
Frederiksborgvej 399
4000 Roskilde