Parallel-sided foil sections are used for centerboards and rudders in sailing dinghy classesand also for struts placed in a fluid flow. The objective of this work is to create a systematic seriesof parallel-sided sections to be used under different conditions, with an emphasis on the sailingdinghies 470, 420 and Optimist. The loss, and surprisingly the gain, in performance relative to 4-digitNACA sections are also investigated. A 2D Reynolds-averaged Navier–Stokes solver is used withthe k-ω SST turbulence model and the gamma transition criterion. A verification study is carriedout based on four grids of systematically varied density, and results compared with experimentaldata on a NACA 64-006 section. The parallel-sided sections are modeled with rational Bézier curveswhose geometrical parameters permit to link the shape of the profile to physical variables, which aresystematically varied. Three Reynolds numbers and two angles of attack are investigated. Systematicplots show the influence of the trailing edge angle and nose radius for the different section families,and the optimum combination is presented in a table. Physical explanations of the trends, and of theexceptions, are given in the paper, using flow visualizations as well as pressure and friction plots.
|Numero di pagine||21|
|Rivista||Journal of Marine Science and Engineering|
|Stato di pubblicazione||Published - 2020|
All Science Journal Classification (ASJC) codes
- Environmental Engineering
- Ocean Engineering