CFD Modeling of Wind Turbine Blades with Eroded Leading Edge

Abstract

The present work compares 2D and 3D CFD modeling of wind turbine blades to define reduced-order models of eroded leading edge arrangements. In particular, following an extensive validation campaign of the adopted numerical models, an initially qualitative comparison is carried out on the 2D and 3D flow fields by looking at turbulent kinetic energy color maps. Promising similarities push the analysis to consequent quantitative comparisons. Thus, the differences and shared points between pressure, friction coefficients, and polar diagrams of the 3D blade and the simplified eroded 2D setup are highlighted. The analysis revealed that the inviscid characteristics of the system (i.e., pressure field and lift coefficients) are precisely described by the reduced-order 2D setup. On the other hand, discrepancies in the wall friction and the drag coefficients are systematically observed with the 2D model consistently underestimating the drag contribution by around 17% and triggering flow separation over different streamwise locations. Nevertheless, the proposed 2D model is very accurate in dealing with the more significant aerodynamics performance of the blade and 30 times faster than the 3D assessment in providing the same information. Therefore the proposed 2D CFD setup is of fundamental importance for use in a digital twin of any physical wind turbine with the aim of carefully and accurately planning maintenance, also accounting for leading edge erosion.