Modeling of Turbulent Atmospheric Flow Around Tubular and Lattice Meteorological Masts

Abstract

This paper presents a numerical study of turbulent atmospheric flow around tubular and lattice meteorological masts and a wind speed and energy uncertainty calculation method based on the numerical results. The flow is described by the Reynolds averaged Navier–Stokes equations, complemented by the shear stress transport turbulence model, with modified constants and source terms added to maintain turbulence properties. ANSYS-CFX 11.0 is used to solve the computational model. The numerical results have been post-processed to account for the wind direction changes during the 10-min-measurement-period, and have been validated with mast data. From the numerical results, a wind speed and energy uncertainty calculation method that takes the wind rose into account is proposed. This technique provides a means to detect incorrectly mounted booms according to the local wind conditions. Most importantly, it produces uncertainty more conservatively than both the International Energy Agency (IEA) recommendations and the IEC-61400-121 (International Electrotechnical Commission) annex G norm. These differences stem from the use of a turbulence model in this paper, which predicts higher flow distortions due to the presence of the mast.