A CFD Study of a Flanged Shrouded Wind Turbine: Effects of Various Flange Surface Types on Output Power

Abstract

There is a global trend to optimize energy harvesting from all energy resources including renewable energy. In this study, the focus is on improving the surface of flanges in flanged shrouded wind turbines to obtain more efficient systems. A CFD approach is utilized for this purpose. All models are identical in the entrance diameter, exit diameter, length of the diffuser, and the height of the flange, but each model is of a different flange surface type. Different surfaces are studied, including a simple surface and some furrowed surfaces. The validation reports that there is a strong correlation between the present study's outcomes and that of previously experimental results. The results show that the models with furrowed surface flange type lead to an increase in the wind velocity when approaching the wind turbine blades. This leads to about 5-7% more output power. Also, the results indicate that the maximum velocity occurs at about 5cm after the shroud entrance. Consequently, it is suggested that the wind turbine should be installed at that location inside the shroud, to obtain the optimum energy harvest.