Print Email Facebook Twitter A physics-based description and modelling of the wall-pressure fluctuations on a serrated trailing edge Title A physics-based description and modelling of the wall-pressure fluctuations on a serrated trailing edge Author Lima Pereira, L.T. (TU Delft Wind Energy) Avallone, F. (TU Delft Wind Energy) Ragni, D. (TU Delft Wind Energy) Scarano, F. (TU Delft Aerodynamics) Date 2022 Abstract A physical description of the flow mechanisms that govern the distribution of the wall-pressure fluctuations over the surface of a serrated trailing edge is proposed. Three main mechanisms that define the variation of turbulent pressure fluctuations across the serrated edge are discussed and semi-empirical models are formulated accordingly. It is shown that the intensity of the wall-pressure fluctuations increases at the tips under the effect of an increased convective velocity as a result of sidewise momentum diffusion. Furthermore, the change of impedance across the edge causes a local reduction of the pressure fluctuations in the vicinity of the trailing edge. Finally, aerodynamic loading over the serrations due to the non-symmetric flow created at different angles of attack establishes secondary flow patterns that induce higher wall-pressure fluctuations over the serration edges. The latter effect is present only for serrations under high aerodynamic loading, while the former ones are observed under any conditions. Semi-empirical models are formulated for predicting the variation of the wall-pressure fluctuations over the serration surface based on the three physical mechanisms described. These models are calibrated and compared against experiments conducted on a symmetric airfoil model at high Reynolds numbers. Subject aeroacousticshydrodynamic noise To reference this document use: http://resolver.tudelft.nl/uuid:c313aec0-c3c3-4948-90a1-a45c745eef73 DOI https://doi.org/10.1017/jfm.2022.173 ISSN 0022-1120 Source Journal of Fluid Mechanics, 938 Part of collection Institutional Repository Document type journal article Rights © 2022 L.T. Lima Pereira, F. Avallone, D. Ragni, F. Scarano Files PDF a_physics_based_descripti ... g_edge.pdf 2.78 MB Close viewer /islandora/object/uuid:c313aec0-c3c3-4948-90a1-a45c745eef73/datastream/OBJ/view