Print Email Facebook Twitter Effect of two-dimensional surface irregularities on swept wing transition Title Effect of two-dimensional surface irregularities on swept wing transition: Forward facing steps Author Rius Vidales, A.F. (TU Delft Aerodynamics) Kotsonis, M. (TU Delft Aerodynamics) Antunes, Alexandre (EMBRAER) Cosin, Renato (EMBRAER) Date 2018-01-01 Abstract An experimental investigation was carried out to examine the effect of two-dimensional Forward Facing Steps surface irregularities, on the laminar-to-turbulent boundary-layer transition on a 45° swept-wing. For the clean reference case, the numerical boundary-layer flow is calculated from pressure measurements, and a thorough linear stability analysis is performed for all variations of Reynolds number and angle of attack. Infrared thermography is employed to determine the transition-front location which is associated to an N-Factor, calculated from the linear stability analysis. The change in the amplification factor ∆N, caused by the addition of the surface irregularity, is analyzed. The reduction in the critical N-factor is observed to correlate with the estimated cross-flow instability vortex core height to step height ratio and the relative step height. The work presented in this paper is part of an ongoing research project to characterize the effect that surface irregularities have on boundary layer transition. The N-method offers an overview of the phenomena related to FFS, capable of guiding future investigations into the underlying flow mechanisms. To reference this document use: http://resolver.tudelft.nl/uuid:05ea5458-3ce6-43e7-91b4-4d9f0d4fc947 DOI https://doi.org/10.2514/6.2018-3075 Publisher American Institute of Aeronautics and Astronautics Inc. (AIAA) Embargo date 2019-09-01 ISBN 9781624105531 Source 2018 Fluid Dynamics Conference Event 48th AIAA Fluid Dynamics Conference, 2018, 2018-06-25 → 2018-06-29, Atlanta, United States Bibliographical note Correction Notice • In section V. Conclusions, the third sentence of the third paragraph should read: “A critical regime in which there was a noticeable change in the transition front pattern, and the transition location rapidly shifted upstream towards the step location, departing in this way from the trend indicated by the clean baseline.” Part of collection Institutional Repository Document type conference paper Rights © 2018 A.F. Rius Vidales, M. Kotsonis, Alexandre Antunes, Renato Cosin Files PDF Rius_Vidales_et_al_2018.pdf 10.87 MB Close viewer /islandora/object/uuid:05ea5458-3ce6-43e7-91b4-4d9f0d4fc947/datastream/OBJ/view