Investigation of a modified IEA 15MW wind turbine including a winglet with a new mid-fidelity acoustic toolchain

Abstract

This paper presents the applicability of a new hybrid tool chain for wind turbine rotor turbulent boundary-layer trailing-edge noise (TBL-TEN) to complex rotor geometries. The research introduces a rapid, high-fidelity 2D CFD/CAA method, which enables the assessment of innovative low-noise profile designs concerning TBL-TEN, coupled with a mid-fidelity extrapolation technique for the 3D analysis, aiming to minimize computational time essential for design processes. This procedure is applied here to compare the changes in performance, load distribution and noise reduction if a winglet is added to a large-scale wind turbine, using the example of the IEA Wind TCP Task 47 15-MW-reference turbine [12]. In the first step, a 3D CFD calculation of the entire turbine is performed in order to derive the local flow parameters and thus the input variables for the 2D CAA. These results for the 2D TEN are then extrapolated for the entire turbine using the fast summation and extrapolation method TAP (Turbine acoustic prediction) [1]. As only data for the TEN is included here, only this noise source for the winglet can be analyzed. For a more complete comparison, a 3D scale-resolving simulation was set up for a static wind tunnel situation in order to be able to qualitatively classify the tip/vortex interaction noise that was not recorded by the procedure mentioned above.