Print Email Facebook Twitter Experiments on a Flettner rotor at critical and supercritical Reynolds numbers Title Experiments on a Flettner rotor at critical and supercritical Reynolds numbers Author Bordogna, G. (TU Delft Ship Hydromechanics and Structures) Muggiasca, S. (Politecnico di Milano) Giappino, S. (Politecnico di Milano) Belloli, M. (Politecnico di Milano) Keuning, J.A. (TU Delft Ship Hydromechanics and Structures) Huijsmans, R.H.M. (TU Delft Ship Hydromechanics and Structures) van 't Veer, A.P. (TU Delft Marine and Transport Technology) Department Marine and Transport Technology Date 2019 Abstract The Flettner rotor is attracting increasing attention as a viable technology for wind-assisted ship propulsion. Nonetheless, the influence of the Reynolds number on the aerodynamic performance of rotating cylinders is still unclear and under debate. The present study deals with a series of wind-tunnel experiments on a large-scale Flettner rotor in which the forces and pressures acting on the cylinder were measured for Reynolds numbers as large as Re=1.0⋅10 6 . The rotating cylinder used in the experimental campaign had a diameter of 1.0 m and span of 3.73 m. The results indicate that the lift coefficient is only affected by the Reynolds number in the critical flow region and below velocity ratio k=2.5. Conversely, in the velocity ratio range 1<k≤2.5, the drag coefficient is markedly influenced by the Reynolds number over the entire range of flow conditions analyzed. The power coefficient scales with the cube of the tangential velocity and it appears to be insensitive to the Reynolds number or whether the cylinder is spun in an air stream or in still air. Subject Magnus effectPressure measurementsRotating cylinderRotor sailWind assisted ship propulsionWind tunnel tests To reference this document use: http://resolver.tudelft.nl/uuid:ae200352-5d8b-4551-900b-3d316cc5fd49 DOI https://doi.org/10.1016/j.jweia.2019.02.006 ISSN 0167-6105 Source Journal of Wind Engineering & Industrial Aerodynamics, 188, 19-29 Part of collection Institutional Repository Document type journal article Rights © 2019 G. Bordogna, S. Muggiasca, S. Giappino, M. Belloli, J.A. Keuning, R.H.M. Huijsmans, A.P. van 't Veer Files PDF 1_s2.0_S0167610518307396_main.pdf 3.74 MB Close viewer /islandora/object/uuid:ae200352-5d8b-4551-900b-3d316cc5fd49/datastream/OBJ/view