Evaluation of Two Performance Prediction Methods for Horizontal-Axis Wind Turbines by Comparison with Experimental Results

摘要

A computer program based on Glauert's blade element theory and a program based on a rotating lifting line theory with nonlinear vortex wake modeling were compared with experimental results for two horizontal-axis wind turbines. In spite of the higher level of sophistication of the lifting line/vortex wake model, the quality of the predicted characteristics of both methods is equal. The blade element theory is far less expensive in computing costs than the rotating lifting line theory. Large differences between theory and experiment can only be explained partly from uncertainties in the aerodynamic characteristics of the basic airfoil sections. For the two different turbine configurations considered, no systematic differences between theory and experiment are found, raising questions about the reliability of the measured data. The rotating lifting line theory suggests that a slightly different optimum blade geometry with wider tip chord than predicted by blade element theory might lead to a performance increase.