Integration of an Unsteady Nonlinear Lifting Line Free Vortex Wake Algorithm in a Wind Turbine Design Framework

摘要

Up to now, the main aerodynamic methods used in almost all wind turbine certification calculations are still based on simple blade element momentum theory models (BEM). Regardless of the large number of empirical corrections, which have been added over the years, BEM simulations can introduce inaccuracies in situations where one or more of its integral assumptions are violated. These inaccuracies can then lead to too large safety factors and an over dimensioning of wind turbine components. In this research, a newly developed tool is presented, as a higher accuracy alternative to BEM methods, for use in horizontal and vertical axis wind turbine certification applications. A robust aerodynamic code, based on the lifting line free vortex wake (LLFVW) formulation was integrated in the open source software QBlade. Through validation test cases and examples of practical applications its accuracy, robustness and efficiency are demonstrated in the following.