Horizontal Axis Wind Turbine Weather Vane Aerodynamic Characteristics: Delayed Detached Eddy Simulation and Experimental Approach

Abstract

The known differential yaw error of horizontal axis wind turbines is clearly linked to weather vane fluctuations, arising out of the deflection of the onrushing wind flow from the rotating blades. Since the problem has not been resolved as the control systems still present this problem, it should be considered as an actual difficulty requiring deeper studies of the weather vane’s aerodynamic features, including the modeling of its deviations. This paper focuses on the computational fluid dynamics and experimental study of the aerodynamic characteristics of the weather vane located on the nacelle top of horizontal axis wind turbines. Computational fluid dynamics simulation is based on the k-ω Shear Stress Transport turbulence model and the Delayed Detached Eddy Simulation. The numerical simulation and laboratory experiment arrangements are demonstrated in detail. The new scientific results obtained during the research include the validation of the numerical experiment, demonstration of the differences in forming the wake structures for the used models on the studied angles of attack and comparison of the mean values of the moment and power spectral densities for all cases, which demonstrated a good correlation between the Delayed Detached Eddy Simulation data and the experiment. The time spent on the preparation of numerical experiments using different models was accurately estimated, to give an understanding of man-hour resources. The obtained moment values for the weather vane are applied for further mathematical modeling of the systems intended for the reduction in the differential yaw error. The applicability of the Delayed Detached Eddy Simulation approach was proved by the simulation of the aerodynamic characteristics of complexly streamlined bodies, but at the same time, it showed an extended calculation period. The results obtained during the study expand upon the experience of using numerical simulation when studying horizontal axis wind turbines and may be used to build mathematical models of yaw control systems.