Filtered Lifting Theory and Application to Wind Turbine Blades

We present a new formulation of the filtered lifting line theory that can be applied to wings with significant changes in chord along the span, such as wind turbine blades. The new formulation can be used as a correction in large-eddy simulations of wind turbine blades using the actuator line model. The correction provides accurate blade loading when using coarse resolutions. We show how the solutions of coarse simulations with the correction match the results from fine resolutions with an optimal actuator line model. The filtered lifting line theory correction can significantly lower the computational expense of large-eddy simulations with an actuator line while providing accurate loading along the blades.