3D Numerical Simulation of Wind Turbines and Fractal Dimension Analysis

Abstract

Wind energy is an important part of renewable energy sources in many countries. In the last decades, the flow simulation for wind turbines have been studied more because it is a very good alternative for producing energy. The community of researches is normally focused on studying behavior and performance of wind farms, spectral contents of the power fluctuations, different methods of quantifying effects of turbulence-generated loads on wind turbine blade, influence of atmospheric turbulence on the fatigue loads. This paper is focused on turbulent flow modeling for 2 and 12 wind model turbines using Large-eddy simulation and Lagrangian-averaged scale-independent dynamic Smagorinsky model. Analyses of vortex behavior along turbine wake and analyses of normalized horizontal velocity profiles behind the wind turbine, as well as fractal dimension calculation for turbulent wake were performed using ImaCalc program. Normalized horizontal velocity profiles were compared with experimental results obtained in wind tunnel in well-known Blind Test. A satisfactory agreement was obtained.