Abstract
An understandingof the blade-element momentum (BEM) theory in comparison with the free-vortex method (FVM) has been developed for the analysis of wind turbine aerodynamics. Understandingthe limitations of BEM methods, used often by the wind turbine community, is very important for the better prediction of turbine power output and blade loads. The BEM theory has been revisited and is compared with vortex methods. The work shows the limits of applicability of the BEM methods and the better flexibility of the FVM to predict the aerodynamics of a wind turbine for a full range of wind turbine operatingstates includingthe vortex ringstate, for turbulent wake state and for yawed flow conditions. It is also shown that linear inflow models used in conjunction with the BEM theory may not be applicable for higher yaw angles. A universal power and thrust coefficient curve with the axial induction factor has also been derived to help understand the operatingflow states of a wind turbine over which the FVM can be applied.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have