Optimizing spanwise lift distributions yacht sails using extended lifting line analysis
2010 (English)In: Journal of Aircraft, ISSN 0021-8669, E-ISSN 1533-3868, Vol. 47, no 6, p. 2119-2129Article in journal (Refereed) Published
Abstract [en]
This paper discusses how to maximize the drive force produced by an upwind sail. It aims to provide a better understanding of the behavior of this force as a function of the heel angle of the yacht and the wind speed. It also discusses the corresponding optimal spanwise loading distributions. An extended lifting line code, based on Weissinger's method, is developed to analyze the performance of an isolated mainsail in upwind conditions. It is extended to account for the heel angle of the yacht via effective angle theory, and an image sail is used to model the influence of the sea surface. Profile drag is modeled using experimental data. The extended lifting line code is validated against wind-tunnel measurements and data from the literature. A second code is then used to optimize the spanwise loading on a mainsail such that the drive force is maximized. Constraints are implemented to ensure positive circulation over the entire span and to limit the sectional loading to realistic values. Finally, the extended lifting line code is inverted to calculate the twist distribution necessary to produce the desired, optimized loading distribution for a given sail planform. The calculated twist distribution is found to be realistic and achievable.
Place, publisher, year, edition, pages
American Institute of Aeronautics and Astronautics Inc. , 2010. Vol. 47, no 6, p. 2119-2129
Keywords [en]
Codes (symbols), Digital storage, Surface waters, Wind, Wind tunnels, Yachts, Drive force, Lifting line, Loading distribution, Sea surfaces, Spanwise lift distribution, Weissinger, Wind speed, Wind tunnel measurements, Loading
National Category
Mechanical Engineering
Identifiers
URN: urn:nbn:se:ri:diva-71816DOI: 10.2514/1.C001011Scopus ID: 2-s2.0-79251527257OAI: oai:DiVA.org:ri-71816DiVA, id: diva2:1838081
2024-02-152024-02-152024-02-15Bibliographically approved