Determination of Ambient Turbulence Intensities for Stratified Atmospheric Flow

Abstract

The purpose of this study is to develop a numerical methodology which will allow the user to generate ambient turbulence intensities with respect to ambient wind speed for various flow conditions over completely flat terrain. The wind characteristics to be used in the analyses will be directly acquired by wind turbine sensors and measurement tower. The main objective of the work is to show that ambient and wake turbulence levels can be well presented with the developed methodology. The time resolution can be easily adjusted by the user. The developed framework has been validated with the nacelle and rotor effective wind speed model based turbulence intensity levels for all defined atmospheric stratification conditions. It is clear that the wake propagation is stimulated quite accurately and dissipation of the wake depends on the wake model in terms of deficit. The results have shown very good consistency with various ambient conditions.