Alois Peter Schaffarczyk

This version is not peer-reviewed. You are already at the latest version Free-wake vortex-ring models are the simplest way of describing a uniformly loaded actuator disc consistently with the Euler equations, i.e. including the radial velocity that accompanies slipstream contraction or expansion.

1. Introduction 1.1. State of the Art Over the past three decades, advancements in wind energy technology have been substantial, largely attributed to the efforts of many scientists and companies. These advancements have resulted in significant reductions in specific electricity production costs, improved overall plant performance, and enhanced efficiency [1].

1 Introduction The development of large wind turbines in the last decades has prompted the creation of new airfoil shapes, dedicated to high-aspect ratio blades, whose design point and characteristics are different from existing airfoils. In particular, these airfoils are generally much thicker, with thickness-to-chord ratios in the order of 20% to 50%, making them more sensitive to early separation of the boundary layer.