Experimental Investigation of a Wind Turbine with Adaptive Camber Rotor Blades under Gusty Conditions

Klaus Schiffmann
This study has the purpose of investigating the performance of the adaptive camber profile (ACP) concept on wind turbine blades. As such, it extends previous studies at the Institute of Fluid Mechanics and Aerodynamics at the Technische Universität Darmstadt in which the load-dependent ACP concept has been examined for two-dimensional flow and for synthetic gust generation. The experiments in this study have been performed on the Berlin Research Turbine (BeRT) at the Technische Universität
more » ... n. Two main goals were formulated in designing the experiments. The first goal was to investigate the ACP performance under fully three-dimensional operating conditions and with realistic turbulence/gust conditions of the inflow. For this, the response of the ACP elements when the turbine operated with a yawed rotor plane was compared to the non-yawed case. The yawed rotor plane resulted in local variations of angle of attack, dependent on both rotation angle and span location, yielding highly unsteady conditions of the onflow. The aim was to examine the ability of the ACP concept to alleviate gust load fluctuations. The second goal was to investigate to what extent the ACP concept was suitable over a larger range of angle-of-attack variations. This was realised by outfitting one rotor blade with three ACP sections, distributed between the root and tip of the blade, since these three positions exhibit very different effective AoA variations. The experiments show that it is favourable to control not only the outer blade area with an ACP mechanism but also the area near the blade root, resulting in a significantly higher overall gust load reduction. A peak load reduction of about 10% could be achieved. On the other hand, local load increase of about 20% could be achieved and this leads to a reduction of load fluctuation amplitude compared with rigid profiles. Based on the findings of this study it can be concluded that the ACP concept, if properly designed and implemented for specific operating conditions, has great potentia [...]
doi:10.25534/tuprints-00013417 fatcat:vwohfsp3dzf2xgmprjiuwnrhxi