ThermoSurf

The leading edge of wind turbine rotor blades is usually prone to degradation due to local impacts such as rain, hail, sand, insects. These surface defects could trigger early laminar-turbulent transition or stall, leading to substantial performance losses. The growing surface defects also promote the fatigue failures. Therefore, early reliable detection of the small surface defects is highly desirable.

This project aims to determine the characteristics of single, localized disturbance elements on the blade surface by analysing the resulting disturbed flow patterns inferred from infrared thermography (IRT) flow visualizations. The type of disturbance (e.g. additive such as debris, or subtractive such as erosion), its location, and a simple geometric description should be determined. To support this, wind tunnel experiments using IRT and particle image velocimetry (PIV) are combined with direct numerical simulations (DNS) to investigate the influence of different disturbance elements on heat transfer and air flow around the blade.