Wind Turbines in ABL-Flow: A Review on Wind Tunnel Studies

Over the last fifteen years a substantial increase in the use of wind energy can be monitored. Presently, several wind farms are planned or under construction in which many wind turbines are arranged as grids. A successful design of a wind farm relies on a number of issues such as: the prediction of wind resource, the rotor-blade design and the optimal siting of the wind turbines. The energy extracted from the flow field by a wind farm depends on the performances of a single wind turbine and the effects of its wake on the wind turbines downstream. The extracted power performances are improving by the enhancement of the near wake research, while far wake research focuses more on the mutual influence among wind turbines and the role played by the terrain the wind farm is located on. Far wake research is important because downstream wind turbines experience a loss of power output as well as an increase of load. At the Meteorological Institute of Hamburg, within the FP7 project WAUDIT, the aim is to deliver quality assurance of wind assessment models. In order to work with reliable data, at the present time we are focusing on the physical modelling of a wind turbine. This paper will review some of the most important previous works analysing the design procedures applied.