Model Experiments in Controlled Conditions

Abstract

Within the framework of the EU FP5 project MEXICO, a sophisticated aerodynamic experiment was designed, and executed in the LLF (Large Scale Low Speed Facility) of the German Dutch Wind tunnel Organisation (DNW). A three bladed rotor model of 4.5 m diameter was designed and manufactured, including a speed controller and pitch actuator. The model was instrumented with 148 Kulite® pressure sensors, distributed over 5 sections of the blades; strain gauges bridges were applied to the three blade roots for the registration of bending moments in two directions. The model was mounted on the wind tunnel 6 components balance, were total forces and moments were measured. Finally a large number of Particle Image Velocimetry (PIV) studies were programmed, to determine the flow field around the rotor, the inflow and near wake, and to track tip vortices. The experiment was designed fort the 9.5*9.5 m2 open test section of the LLF. Detailed studies were executed to enable tunnel corrections on the measurements. The measurement programme was executed in December of 2006. All planned measurement data was obtained, and forms a 100 GB database of detailed aerodynamic information, available to all consortium members. Initial data processing has been performed which will lead to improvements of design methods and to validate CFD methods.