Wind Resource Assessment In Complex Terrain With Limited Data

TitleWind Resource Assessment In Complex Terrain With Limited Data
Publication TypeConference Paper
Year of Publication2012
Date Published05/2012
Conference Name7th International Conference of the Croatian Society of Mechanics
Publication Languageeng
AuthorsTuran, K, Torlak, M, Hadżiabdić, M
Publisher7th International Conference of the Croatian Society of Mechanics
Place PublishedZadar/ Croatia

The wind energy is important component in energy diversification and amount of electrical energy produced by wind is continuously increasing. In the early days of the modern wind farming, wind farms were limited to flat-terrain or off-shore regions where prediction of wind-energy potential is a relatively easy task.  Today, wind farms are built also in areas of greater orographic complexity, for which commonly used linear mathematical models of the fluid flow equations are not reliable. Orographic complexity of terrain causes complex flow patterns with separation and recirculation, three-dimensionality effects (e.g. cross flow), strong pressure gradient, strong forcing and related unsteadiness. These phenomena determine locally prevailing wind regimes that are important for proper wind resource assessment and turbine micro-sitting. Hence, the wind engineering community turns their attention to Computational Fluid Dynamics (CFD) as a solution for the problems of wind assessment on complex terrains. CFD is based on numerical solution of Navier-Stokes equations that completely describe the flow in all regimes. CFD for wind and environmental engineering relies on the conventional Reynolds-averaged Navier–Stokes (RANS) approach which includes turbulence models of different complexity. While linear models are based on linearised forms of the fluid flow equations and cannot predict phenomena such as separation, RANS methods account for non-linearity of the flow and in principle can capture flow unsteadiness.The present study explores possibility of combining results of linear (WASP) and non-linear (CFD) models in order to obtain more reliable estimation of wind energy in complex terrain and in situation where limited measurement data exists.