Engineering Models for Wind Turbines

The design of a wind turbine (WT) involves several computations of the blade and rotor aerodynamics and for a wide range of conditions. Even if CFD based on the Navier-Stokes equations is nowadays the dominant tool for WT analysis, there is room for efficient engineering methods to provide first estimates of WT performance. These efficient methods allow for computations at different operating conditions as well as a range of blade geometries. In this project differentengineerings methods are implemented, analysed and compared with 3D CFD simulations and experimental results. Most of the methods can make use of a database of experimental or CFD-generated data for the sectional aerodynamics of the blades.


The methods developed in this project include the Blade Element Momentum method with prescribed (Kockure-Tangler and Helical) or free wakes methods. These methods account for tip losses, non uniform inflow profiles and tower shadow effects. The implemented free wake method involves a discretised time marching method coupled with a panel method to account for the presence of the WT tower.


These methods are applied on a range of rotors varying from small wind tunnel models to 10 MW off shore wind turbines. The prescribed and free wake models provide, in addition of the performance characteristics, predictions of the wake shape and the vortex core locations, as shown in the following figure

Wake by free wake model of Jur



George Barakos - Professor,